Here’s what we know about the deadly crash of a Russian airliner in Egypt that killed all 224 people on board Saturday. (Monica Akhtar/The Washington Post) 
 
 Here’s what we know about the deadly crash of a Russian airliner in Egypt that killed all 224 people on board Saturday. (Monica Akhtar/The Washington Post) 
 
 A public quarrel erupted Monday over the cause of the weekend plane crash in Egypt that killed 224 people, and it pitted the airline that operated the Airbus jet against the Russian government. 
 
 Metrojet, a small Russian airline scrambling to protect its reputation after the devastating crash, found itself at odds with government officials who wanted to contain speculation about what led to the deadliest civil aviation disaster in Russia’s history. 
 
 [Sinai increasingly restive and unstable] 
 
 When a senior Metrojet official declared Monday that the company had ruled out pilot error or a technical malfunction as the reason for the crash, the government responded with a swift rebuke. 
 
 “That statement is premature and is based on no real facts,” Alexander Neradko, the head of Russia’s Federal Air Transport Agency, said in a television interview from Egypt. 
 
 Investigators have not said whether a technical malfunction, pilot error or an act of terrorism caused the Airbus A321-200 to disintegrate over Egypt’s troubled Sinai Peninsula on Saturday, scattering debris over seven square miles of desert. Investigators have retrieved the plane’s black boxes but have not reviewed them yet, Neradko said in the interview. 
 
 “Yes, we know that components of the plane have been thrown over a wide area. That says that the breakup took place in the air, at a high altitude,” he said. “But it is very premature to talk about the reasons. I would like to call on the aviation community to abstain from premature statements.” 
 
 While an Egyptian affiliate of the Islamic State seized the opportunity to claim responsibility for the plane crash Saturday, Russian officials remained skeptical. 
 
 The claim led some international carriers to reroute flights away from the Sinai, though defense experts have raised strong doubts about whether the Islamic State could have missile systems capable of hitting an airliner at 31,000 feet. 
 
 In Washington, James R. Clapper Jr., the director of national intelligence, said that there was no “direct evidence of terrorist involvement yet” but that it cannot be disregarded. “It’s unlikely, but I wouldn’t rule it out,” Clapper told reporters. 
 
 Prevailing wisdom holds that once an airplane reaches cruising altitude, it’s clear sailing, but there have been at least half a dozen times when a commercial jetliner has fallen to pieces without help from a bomb or a missile. 
 
 [What would cause a plane to break up in midair?] 
 
 : Russia mourns after airliner crashes in Egypt: None of the 224 people on board a Russian aircraft survived after it went down en route from an Egyptian resort area to St. Petersburg. ( / ) 
 
 What happened to the Metrojet flight is a riddle whose answer is fraught with consequences, either implicating Russia’s troubled airline industry or suggesting that Russia was targeted by terrorists, possibly because of the country’s intervention in Syria’s civil war. 
 
 “On the one hand, saying that it was ISIS might be convenient from the point of view that it’s not actually lax maintenance and safety standards” that caused the crash, said Alex Kazbegi, a transport analyst at Renaissance Capital, using an acronym for the Islamic State. 
 
 “But on the other hand, saying it was ISIS could be saying it was actually a response to Russia being in Syria, which may also be considered politically unacceptable.” 
 
 Russian President Vladi­mir Putin called the accident “a great tragedy” Monday. 
 
 “Everything must be done to create an objective picture of what happened so that we know what happened and react accordingly,” Putin told Transport Minister Maxim Sokolov during a televised briefing on the investigation. 
 
 As the investigation continues, there are unmistakable signs that Metrojet is in the crosshairs. 
 
 Investigators this weekend opened a probe for criminal negligence in the crash and searched Metrojet’s offices. Russia’s Federal Labor Agency announced Monday that the airline had not paid its employees in the past two months, indicating financial problems in the company. And a state-owned television channel broadcast an interview with the pilot’s wife, who said her husband had complained about poor maintenance on the plane. 
 
 Metrojet’s embattled leadership mounted a public defense Monday at a news conference in Moscow. 
 
 Alexander Smirnov, the deputy general director of the airline, said no combination of factors, including bad fuel or engine failure, could have led the plane to break up in midair. Metrojet officials also said that the plane was regularly reviewed for signs of structural weakening and argued that although the company had withheld wages recently, that did not affect safety standards. 
 
 “The only explanation could be a mechanical impact on the aircraft,” Smirnov said. He declined to elaborate as to what such an impact could have been. 
 
 Though Smirnov discounted the possibility that the Metrojet plane could have fatally malfunctioned, it would not be unprecedented. 
 
 [Egypt’s upheaval has transformed much of the Sinai into a no-go zone] 
 
 Planes climb to a cruising altitude of six to seven miles above the Earth’s surface because there, the air is far thinner, and against that lessened resistance they can fly faster and use less fuel. 
 
 When they reach that altitude, however, they must maximize the air pressure in the cockpit and cabin — and that puts stress on any component that has weakened over time. 
 
 “Typically, if there was that type of defect, you would expect it to manifest just as it reached the peak” altitude, said Steve Wallace, a former crash investigator for the Federal Aviation Administration. 
 
 In 1988, a hole opened in the fuselage of an Aloha Airlines plane in Hawaii, sucking out a flight attendant. Metal fatigue was blamed in 2002 when China Airlines Flight 611 disintegrated after takeoff from a Taiwan airport, killing all 225 people on board. 
 
 “That airplane had an improper repair after a tail strike,” Wallace said, “and I think this Russian airplane that was in the accident had had a tail strike.” 
 
 The Aviation Safety Network reported that the Metrojet plane suffered a “tail strike” in 2001, a type of incident in which an airplane’s tail hits the runway. The damage took three months to repair, but the jet was certified as airworthy this year by regulators in Ireland, where it was registered. 
 
 The Metrojet crash comes as Russian airlines are facing an economic crunch that has forced Transaero, the country’s second-largest airline, to file for bankruptcy. Russia’s aviation authorities grounded Transaero flights recently over concerns that the airline could not maintain safety standards. 
 
 But historically, Kazbegi noted, Russia’s regional and charter airlines have suffered the majority of the country’s air disasters. And with the recent devaluation of the ruble and the country’s economic crisis, they are struggling to make ends meet. 
 
 Travel to Egypt has declined by about 20 percent this year, said Maya Lomidze, executive director of Russia’s Association of Tour Operators. For charter airlines such as Metrojet, that has meant canceling or rescheduling flights, among other measures. 
 
 “Everyone has been saving in one way or another,” she said. 
 
 Meanwhile, thousands of Russian tourists in Egypt still have to find their way home. 
 
 “Some people are panicked; of course there is fear; many people are still in shock,” Lomidze said. “People are afraid to fly. But one way or another, they have to get home.” 
 
 Halsey reported from Washington. Erin Cunningham and Heba Habib in Cairo, Daniela Deane in London, and Brian Murphy and Ellen Nakashima in Washington contributed to this report. 
 
 Read more: 
 
 Al-Qaeda in Syria calls for revenge attacks on Russia 
 
 Russia defends Syria airstrikes amid claims of blows to U.S.-backed rebels 
 
 Today’s coverage from Post correspondents around the world ||||| Media playback is unsupported on your device Media caption Richard Westcott reports on the ongoing investigation into the crash 
 
 The Russian airline Kogalymavia has blamed "external influence" for Saturday's Sinai plane crash which killed 224 people. 
 
 A senior airline official said: "The only reasonable explanation is that it was [due to] external influence." 
 
 An investigation by aviation experts using data from the aircraft's "black boxes" has yet to give its conclusions. 
 
 The head of Russia's Federal Aviation Agency said it was premature to speculate on the cause of the crash. 
 
 "This kind of talk is... not based on any proper facts," Aleksandr Neradko said on Russian TV. 
 
 Egyptian President Abdel Fattah el-Sisi also said in an interview with the BBC that it was too early to say what had caused the crash. 
 
 He called a claim from jihadis allied to the so-called Islamic State (IS) group that they had brought down the plane "propaganda". 
 
 "This is one way to damage the stability and security of Egypt and the image of Egypt," he said. 
 
 Media playback is unsupported on your device Media caption President Sisi said the area of Sinai concerned was "under our full control" 
 
 James Clapper, the US director of national intelligence, said there was no "direct evidence of any terrorist involvement yet" adding: "It's unlikely, but I wouldn't rule it out." 
 
 Russian President Vladimir Putin has described the crash as an "enormous tragedy" and expressed his condolences to the families of the victims. 
 
 "Without any doubt, everything must be done to create an objective picture of events so that we know what happened and can react accordingly," he said. 
 
 At a news conference in Moscow, the deputy director of the airline, which was later renamed Metrojet, ruled out a technical fault and pilot error. 
 
 "The only [explanation] for the plane to have been destroyed in mid-air can be specific impact, purely mechanical, physical influence on the aircraft," Alexander Smirnov said. 
 
 "There is no such combination of failures of systems which could have led to the plane disintegrating in the air," he added. 
 
 Another airline official acknowledged that there had been previous damage to the plane's tail in 2001 during take-off. 
 
 But he said that the damage had been repaired, and was not thought to be a factor in the crash. 
 
 However, the widow of the plane's co-pilot told Russian TV her husband had complained about the aircraft's technical condition. 
 
 Media playback is unsupported on your device Media caption Sarah Rainsford reports from a morgue in St Petersburg where bodies are being identified 
 
 The Airbus 321 lost speed and started descending rapidly, and the crew made no attempt to get in contact and report about the situation on board, Mr Smirnov added. 
 
 The bodies of 144 of those killed in the crash have been flown back to the Russian city of St Petersburg, where the plane had been headed from the Egyptian resort of Sharm el-Sheikh. 
 
 Russian Emergency Situations Minister Vladimir Puchkov said that searches in a 20-sq-km (7.7-sq-Mile) area around the crash site had ended and that a 30-sq-km area was now being searched. 
 
 Mr Puchkov said searches would not end until all the bodies have been recovered, AP reports. 
 
 The plane was carrying 217 passengers, including 25 children, and seven crew members - mostly Russians. 
 
 Timeline: the course of flight KGL9268 
 
 05:58 Egyptian time (03:58 GMT): Flight leaves Sharm el-Sheikh, a statement from the Egyptian cabinet says 
 
 06:14 Egyptian time (04:14 GMT): Plane fails to make scheduled contact with air traffic control based in Larnaca, Cyprus, according to Sergei Izdolsky, an official with Russia's air transport agency 
 
 06:17 Egyptian time, approx (04:17 GMT): Plane comes down over the Sinai peninsula, according to Airbus 
 
 11:12 Egyptian time (09:12 GMT): Flight had been due to land in St Petersburg's Pulkovo airport ||||| ‘Only explainable cause is physical impact on the aircraft,’ says Metrojet official, ruling out technical fault or mistake by crew 
 
 Russian airliner Metrojet says Saturday’s plane crash in Egypt, which killed all 224 people on board, was not caused by technical problems or pilot error. 
 
 The flight from the Egyptian beach resort of Sharm el-Sheikh to St Petersburg broke up over the Sinai peninsula. 
 
 
 
 “We rule out a technical fault of the plane or a pilot error,” said Alexander Smirnov, deputy general director of Metrojet. “The only explainable cause is physical impact on the aircraft.” Pressed for an explanation about what could have caused this impact, Smirnov said he was not at liberty to discuss details because the investigation was ongoing. 
 
 
 
 The head of the Russian aviation agency said it was premature of Metrojet to comment on the possible cause since investigators do not have enough data to reach any conclusions. Alexander Neradko, who has arrived in Cairo, said fragments and the contents of the black boxes would need to be studied first. 
 
 According to Smirnov, the plane dropped 186mph in speed and about 5,000ft in altitude one minute before it crashed. “This isn’t flying, it’s falling. Apparently, the plane sustained damage before this [and] that became the reason for the fall,” Smirnov said. 
 
 
 
 The fact that the crew did not attempt to contact ground services meant the plane had “completely lost operational capabilities when the catastrophic situation began to develop” and was not able to put out a distress signal, Smirnov said. Passengers most likely died from stresses experienced after the plane broke up, he added. 
 
 
 
 A source in the Egyptian committee analysing the plane’s black box recorders told Reuters the plane had not been struck from the outside and the pilot did not make a distress call before it disappeared from radar. The source declined to give more details but based his comments on the preliminary examination of the boxes. 
 
 Aviation experts have speculated that a sudden mechanical failure or an explosion could have been to blame. 
 
 
 
 On Saturday, a militant group affiliated to Islamic State in Egypt claimed responsibility for bringing down the jet, but Egypt and Russia disputed the claim, suggesting militants in northern Sinai, where Egypt has been fighting an Islamic insurgency, did not have the weaponry to hit a flight at 9,000 metres (31,000ft). 
 
 However, Zack Gold, a regional expert on Sinai security, pointed out on Sunday that the militant’s group’s statement “said they were responsible for downing the plane, not shooting it down”. 
 
 Gold said: “A legitimate Isis-supporting account in Sinai said: ‘Why is everyone talking about shooting it down, why is no one talking about a bomb or suicide bomber on board’.” 
 
 If a bomb had been planted on the plane, it would suggest security systems at Sharm el-Sheikh airport had been infiltrated or compromised, which would raise a whole range of other questions, he said. Gold added that there had been nothing to support the claim so far, such as a pre-mission video of a suicide attacker. 
 
 “The group does not have a history of major fabrications, but at the same time it’s curious that they would make this claim without providing any kind of evidence. They have military capabilities, but to carry out this kind of terrorism [on a plane] they would have to display organisation they haven’t shown [before].” 
 
 A Kremlin spokesman, Dmitry Peskov, said on Monday no causes could be ruled out. When asked about a possible terrorist attack, he asked journalists to wait for investigators’ results. 
 
 
 
 The Russian president, Vladimir Putin, who has not appeared in public since the plane went down, adopted a more active role in the crash’s aftermath on Monday. The Kremlin website published a photograph of him meeting his transport minister, Maksim Sokolov, who is leading the commission investigating the disaster. 
 
 Putin called for “maximum attention” to be given to the families of the victims, declaring: “We are with you in heart and spirit,” news agency Interfax reported. He also called for an “objective picture” of the incident to be determined so that “we know what happened and can react accordingly”. 
 
 The aircraft, built in 1997, suffered a tail strike in 2001, where the rear end of the plane touches the runway on takeoff. It underwent extensive repairs. On Monday, Oksana Golovina, a spokeswoman for the company that owns Metrojet, said the repaired area had been inspected in 2014. “The airplane was 100% ready to fly, in working order, otherwise it wouldn’t have taken off,” she said. 
 
 
 
 Despite additional checks imposed by the state transport regulator, Golovina said Metrojet would continue its flights to Egypt. Two of its remaining planes have undergone safety checks and two are in the process of being checked, she said. 
 
 “If we for a second doubted the flight readiness of our planes or our personnel, we would stop flights,” Golovina said. “We are confident our flights are in working order, we are confident our personnel’s capabilities meet or even exceed international standards.” 
 
 The dead, including more than 20 children, were all Russian apart from four Ukrainians and one person from Belarus. Early on Monday, the bodies of 140 victims of the crash arrived back in St Petersburg. Their remains were to be taken in a motorcade to a crematorium for identification, which will begin later in the day, according to Russia’s emergency ministry. ||||| ST. PETERSBURG, Russia (AP) — The latest developments after a Russian passenger plane crashed in Egypt's Sinai Peninsula, killing all 224 people on board Saturday (all times local). 
 
 Russian Ministry for Emergency Situations employees stand preparing to load the bodies of the victims from the ministry's plane in St. Petersburg, Russia, Monday, Nov. 2, 2015. Metrojet's Airbus A321-200... (Associated Press) 
 
 Friends Ekaterina Ivanova and Sergei Igolkin, of St. Petersburg, Russia, sit in a seaside cafe after arriving on a Metrojet flight, in Sharm el-Sheikh, south Sinai, Egypt, Sunday, Nov. 1, 2015. They said... (Associated Press) 
 
 People light candles during a day of national mourning for the plane crash victims at Dvortsovaya (Palace) Square in St. Petersburg, Russia, on Sunday, Nov. 1, 2015. The Metrojet charter crashed Saturday... (Associated Press) 
 
 Russian Ministry for Emergency Situations employees carry hand-barrows preparing to load the bodies of the victims from the ministry's plane in St. Petersburg, Russia, Monday, Nov. 2, 2015. Metrojet's... (Associated Press) 
 
 Russian investigators stand near debris, luggage and personal effects of passengers a day after a passenger jet bound for St. Petersburg in Russia crashed in Hassana, Egypt, on Sunday, Nov. 1, 2015. The... (Associated Press) 
 
 People gathered to light candles during a day of national mourning for the plane crash victims at Dvortsovaya (Palace) Square in St. Petersburg, Russia, on Sunday, Nov. 1, 2015. The Metrojet charter crashed... (Associated Press) 
 
 Russian Ministry for Emergency Situations employees walk past a truck preparing to load the bodies of the victims from the ministry's plane in St. Petersburg, Russia, Monday, Nov. 2, 2015. Metrojet's... (Associated Press) 
 
 People hold candles during a day of national mourning for the plane crash victims at Dvortsovaya (Palace) Square in St. Petersburg, Russia, on Sunday, Nov. 1, 2015. The Metrojet charter crashed Saturday... (Associated Press) 
 
 An Egyptian military helicopter flies over wreckage of the Metrojet passenger plane bound for St. Petersburg, Russia that crashed Saturday, in Hassana, Egypt, Sunday, Nov. 1, 2015. The Russian jetliner... (Associated Press) 
 
 A woman woman releases a white bird in memory of the victims during a day of national mourning for the plane crash victims at Dvortsovaya (Palace) Square in St. Petersburg, Russia, on Sunday, Nov. 1,... (Associated Press) 
 
 Russian Ministry for Emergency Situations employees stand next to a truck preparing to load the bodies of the victims from the ministry's plane in St. Petersburg, Russia, Monday, Nov. 2, 2015. Metrojet's... (Associated Press) 
 
 2 p.m. 
 
 A Metrojet official says its plane crew did not send a distress call and did not contact Egyptian traffic controllers before the plane crashed into the Sinai. 
 
 Viktor Yung, a deputy director general at the Russian airline, spoke Monday at a news conference in Moscow. His comments directly contradict those of Egyptian officials, who say the doomed plane's pilot had reported a technical problem to air traffic controllers and wanted to make an emergency landing at the nearest airport. 
 
 Another Metrojet official, Alexander Smirnov, on Monday ruled out technical faults or pilot error as a cause of Saturday's crash, saying it had to be due to "an external impact on the plane." 
 
 All 224 people aboard the plane were killed. 
 
 ___ 
 
 1:45 p.m. 
 
 Russia's emergency situations minister has examined the black boxes from Saturday's crash of a Russian plane in Egypt and says they are in a good condition. 
 
 Russian news agencies on Monday quoted Vladimir Puchkov as saying that so Russian officials were shown the black boxes found at the site of the crash in the Sinai Peninsula. 
 
 Investigators have so far refrained from naming the cause of the crash but Metrojet, the Russian company operating the plane, on Monday ruled out technical faults or pilot error as a cause of the crash. 
 
 All 224 people aboard the plane were killed. 
 
 ___ 
 
 1:30 p.m. 
 
 A top official at Metrojet says its plane dropped 300 kph (186 mph) in speed and 1.5 kilometers (about 5,000 feet) in altitude one minute before it crashed into Egypt's Sinai Peninsula. 
 
 Alexander Smirnov, the deputy general director of Metrojet, also told reporters Monday in Moscow that no technical fault could have caused the Airbus A320-200 to break up in the air. He says the cause of Saturday's crash "could only have been a mechanical impact on the plane" in the air. 
 
 Russian investigators say the plane broke up at high altitude over the Sinai Peninsula but have so far refrained from naming possible causes. All 224 people aboard were killed. 
 
 ___ 
 
 1:10 p.m. 
 
 A top official at Metrojet, the Russian airline company whose charter flight crashed Saturday in Egypt, says the plane lost speed right before the crash. 
 
 Alexander Smirnov, the deputy general director of Metrojet, also told reporters Monday in Moscow that no technical fault could have caused the Airbus A320-200 to break up in the air. He says the cause of the crash "could only have been a mechanical impact on the plane" in the air. 
 
 Russian investigators say the plane broke up at high altitude over the Sinai Peninsula but have so far refrained from naming possible causes. All 224 people aboard were killed. 
 
 ___ 
 
 1 p.m. 
 
 A top official at Metrojet, the Russian airline company whose flight crashed Saturday in Egypt, is insisting that a technical fault could not have caused the crash. 
 
 Alexander Smirnov, the deputy general director of Metrojet, told reporters Monday in Moscow that no technical fault could have caused the Airbus A320-200 to break up in the air. He says the cause of the crash "could only have been a mechanical impact on the plane" in the air. 
 
 Russian investigators say the plane broke up at high altitude but have so far refrained from naming possible causes. 
 
 The Metrojet crashed Saturday morning 23 minutes after taking off from Sharm el-Sheikh, killing all 224 on board, the vast majority of them Russians. 
 
 ___ 
 
 11:50 a.m. 
 
 A Russian official says forensic experts have begun identifying the bodies of the 224 victims of the Metrojet plane crash in Egypt. 
 
 Yulia Shoigu, chief of the emergency situations ministry's psychological service, made the comment Monday in televised remarks. Russia has sent over 100 emergency workers and aviation experts to help Egypt examine the crash site in the Sinai Peninsula. French, German and Airbus aviation teams are also helping the investigation. 
 
 A Russian government plane on Monday brought 140 bodies of plane crash victims to St. Petersburg, where most of the passengers were from. Another plane will be taking more crash victims' bodies to St. Petersburg from Cairo late Monday night. 
 
 ___ 
 
 10:40 a.m. 
 
 Russia's emergency situations minister Vladimir Puchkov says the search for the bodies of victims of the plane crash in Egypt will wrap up in a day. 
 
 Puchkov tells a televised press conference Monday that the search in the Sinai Peninsula should wrap up by 10 p.m. Monday. 
 
 The Metrojet Airbus A320-200 crashed Saturday morning 23 minutes after taking off from Sharm el-Sheikh, killing all 224 on board. Most were Russian and many were from St. Petersburg. 
 
 A Russian government plane took the first 140 bodies from Egypt to St. Petersburg early Monday. Puchkov said another plane will travel from Egypt to St. Petersburg on Monday evening to bring more bodies of plane crash victims.
– An ominous development in Saturday's crash of a Russian plane in Egypt: The airline says pilot error or technical problems could not have caused the crash of Kogalymavia Flight 9268, leaving unspecified "external activity" in the air as the only possible cause, reports the BBC, which notes that an ISIS affiliate is active in the area where the plane went down and that Moscow hasn't ruled out terrorism as a cause. "The only [explanation] for the plane to have been destroyed in mid-air can be specific impact, purely mechanical, physical influence on the aircraft," says airline deputy director Alexander Smirnov. "There is no such combination of failures of systems which could have led to the plane disintegrating in the air." He says that contrary to some reports, the flight did not send out a distress signal or contact air traffic controllers before it broke up midair, reports the AP. Russian officials, meanwhile, say they've gotten a look at the plane's black boxes and they're in good condition, per the AP. The bodies of around 140 of the 224 victims arrived back in St. Petersburg, the doomed flight's destination, early on Monday, reports the Guardian. A state of official mourning has been declared in the city for what officials say is Russia's deadliest aviation disaster, the Washington Post reports. The Post also reports that major carriers, including KLM and Air France, have decided to avoid flying over the Sinai Peninsula until the cause of the crash is known, though United, the only American carrier to fly over the Sinai, says it does "not see a need" to change its routes immediately.