Visitors stand near a signboard showing the distance to the North Korea's capital Pyongyang and to South Korea's capital Seoul from Imjingang Station near the border village of the Panmunjom in Paju,... (Associated Press) 
 
 SEOUL, South Korea (AP) — North Korea ignored U.N. resolutions by firing a medium-range ballistic missile into the sea on Friday, Seoul and Washington officials said, days after its leader Kim Jong Un ordered weapons tests linked to its pursuit of a long-range nuclear missile capable of reaching the U.S. mainland. 
 
 South Korea's Joint Chiefs of Staff said in a statement that the missile fired from a site north of Pyongyang flew about 800 kilometers (500 miles) before crashing off the North's east coast. It was the first medium-range missile launched by the North since it fired two in April 2014, said a South Korean defense official, requesting anonymity citing department rules. 
 
 A senior U.S. defense official said the missile appeared to be a Rodong type fired from a road-mobile launcher. The test violated multiple U.N. Security Council resolutions that ban North Korea from engaging in any ballistic and nuclear activities, said the official, speaking on condition of anonymity because he was not authorized to discuss the matter publicly. 
 
 The launch came as North Korea condemned ongoing annual South Korean-U.S. military drills that it sees as an invasion rehearsal. The two sets of drills are the largest ever, in response to the North's nuclear test and long-range rocket launch earlier this year. One of the drills, computer-simulated war games, was to end later Friday while the other, field training, is to continue late April. 
 
 In recent weeks, North Korea threatened pre-emptive nuclear strikes against Washington and Seoul and fired short-range missiles and artillery into the sea in an apparent anger over the drills and tough U.N. sanctions imposed over its nuclear test and rocket launch. 
 
 South Korea's military said its surveillance equipment detected the trajectory of a suspected second missile fired from the same site. A Joint Chiefs of Staff statement said the object later disappeared from South Korean radar at an altitude of 17 kilometers (10 miles) and that it was trying to find out if a missile had been fired or something else was captured by the radar. 
 
 No fresh sanctions on the North were expected for Friday's launch. The U.N. Security Council slapped the country with sanctions each time when it conducted nuclear tests and long-range rocket launches, but it usually responded to short- and medium-range ballistic launches with statements criticizing them. 
 
 On Tuesday, North Korea's state media said Kim had ordered tests soon of a nuclear warhead and ballistic missiles capable of carrying warheads. Kim issued the order while overseeing a successful simulated test of a re-entry vehicle aimed at returning a nuclear warhead into the atmosphere from space so it could hit its intended target, according to the North's Korean Central News Agency. 
 
 Taewoo Kim, a military expert at the South's Konyang University, said it is likely that Friday's launch was a test of a re-entry vehicle mounted on the purported Rodong missile. 
 
 The North Korean missile fired may not be a Rodong but a long-range missile whose launch angle was altered so that it didn't fly its full range, said Kwon Sejin, a professor at the Korea Advanced Institute of Science and Technology in South Korea. He said the missile may have carried an empty warhead, which contains trigger devices but lack plutonium or uranium, to see if it can survive the fiery re-entry and detonate at the right time. 
 
 Outside experts said it is a key remaining technology that North Korea must master to achieve its goal of developing a long-range missile capable of hitting the U.S. mainland. South Korean defense officials said earlier this week that North Korea had yet to develop the re-entry technology, so it still does not have a functioning intercontinental ballistic missile. 
 
 The South Korean defense official said Seoul has no immediate plans to try to retrieve debris of the missile that appeared to have landed in the waters inside Japan's air defense identification zone. South Korea did not retrieve missile parts after the North's 2014 launches either. 
 
 North Korea is thought to have a small arsenal of atomic bombs, but South Korean officials and many outside experts say they are not small enough to place on missiles that can strike faraway targets. 
 
 Analyst Lee Choon Geun at South Korea's state-funded Science and Technology Policy Institute said the North can probably place nuclear warheads on its shorter-range Scuds and medium-range Rodong missiles, which would put South Korea and Japan under its striking range. Other analysts question that. 
 
 The North began to develop ballistic missiles in the 1970s by reverse-engineering Soviet-made Scuds it acquired from Egypt. After several failures it put its first satellite into space aboard a long-range rocket launched in December 2012. Its second successful satellite launch occurred this February. The U.N., the U.S. and others say the launches were a banned test of missile technology. Ballistic missiles and rockets used for satellite launches share similar bodies, engines and other technology. 
 
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 Associated Press writer Lolita C. Baldor in Washington, D.C. contributed to this report. ||||| SEOUL (Reuters) - North Korea fired two ballistic missiles on Friday, one of which flew about 800 km (500 miles) while the other exploded shortly after launch, U.S. officials said, as the isolated state stepped up its defiance of tough new U.N. and U.S. sanctions. 
 
 U.S. officials told Reuters the medium-range missiles appeared to be fired from road-mobile launchers. 
 
 One missile, fired from north of the capital, Pyongyang, flew across the peninsula and into the sea off the east coast early Friday morning, South Korea’s Office of the Joint Chiefs of Staff said in a statement. 
 
 That would mark North Korea’s first test of a medium-range missile, one of which was capable of reaching Japan, since 2014. 
 
 U.S. officials, speaking on condition of anonymity, said the second missile flew a short period before exploding. 
 
 South Korea did not confirm the type of missile but U.S. officials said they were medium-range ballistic missiles. 
 
 A range of 800 km was likely beyond the capability of most short-range missiles in North Korea’s arsenal. The North’s Rodong missile has an estimated maximum range of 1,300 km (810 miles), according to the South’s defense ministry. 
 
 North Korea’s action provoked a barrage of criticism and appeals. 
 
 Chinese Foreign Ministry spokesman Lu Kang urged it to abide by U.N. resolutions and not do anything to exacerbate tensions. 
 
 U.S. Defense Secretary Ash Carter said the United States was “analyzing the results of those launches,” but called on Beijing to use its influence over Pyongyang. 
 
 “China could do a lot more,” Carter said, adding Beijing should seek a nuclear-free North Korea. 
 
 The U.S. State Department in a statement urged North Korea to focus on taking concrete steps toward fulfilling its international commitments and obligations. 
 
 North Korean leader Kim Jong Un (L) speaks at an event declaring the construction of Ryomyong Street, in this photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang on March 18, 2016. REUTERS/KCNA 
 
 Japan lodged a protest with North Korea through its embassy in Beijing, Prime Minister Shinzo Abe told parliament. 
 
 “Japan strongly demands North Korea to exercise self-restraint and will take all necessary measures, such as warning and surveillance activity, to be able to respond to any situations,” Abe said. 
 
 South Korea’s Unification Ministry said Pyongyang should focus on improving the lives of its people and that provocative actions would help nothing. 
 
 NUCLEAR WARHEADS 
 
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 North Korea often fires missiles during periods of tension on the Korean peninsula or when it comes under pressure to curb its defiance and abandon its weapons programs. 
 
 Last week, the North fired two short-range missiles into the sea off its east coast and its leader Kim Jong Un ordered more nuclear weapons tests and missile tests. 
 
 That came after North Korean media said the North had miniaturized nuclear warheads to fit on ballistic missiles and quoted Kim as calling on the military to prepare for a “pre-emptive nuclear strike” against the United States and South Korea. 
 
 U.S. President Barack Obama imposed new sanctions on North Korea on Wednesday over its nuclear test and satellite launch. The sanctions freeze North Korean government assets in the United States, bans U.S. exports to, or investment in, North Korea, and expands a U.S. blacklist to anyone, including non-Americans, who deals with North Korea. 
 
 North Korea conducted its fourth nuclear test on Jan. 6 and launched a long-range rocket on Feb. 7 in defiance of existing U.N. Security Council resolutions. 
 
 The North has called annual joint drills by U.S. and South Korean troops that began on March 7 “nuclear war moves” and threatened to wipe out its enemies. 
 
 The U.S. and South Korea remain technically at war with the North because the 1950-53 Korean War ended in an armed truce instead of a peace agreement. In recent weeks, the two Koreas have suspended economic ties over the mounting tensions. 
 
 South Korea and U.S. officials this month began discussions on deploying the advanced anti-missile Terminal High Altitude Area Defence (THAAD) system to the U.S. military in the South, despite Chinese and Russian objections. 
 
 On Wednesday, North Korea’s supreme court sentenced a visiting American student to 15 years of hard labor for crimes against the state, a punishment Washington condemned as politically motivated.
– North Korea ignored UN resolutions by firing a medium-range ballistic missile into the sea on Friday, Seoul and Washington officials say, days after leader Kim Jong Un ordered weapons tests linked to its pursuit of a long-range nuclear missile capable of reaching the US mainland, the AP reports. South Korea's Joint Chiefs of Staff said in a statement that the missile fired from a site north of Pyongyang flew about 500 miles before crashing off the North's east coast. It was the first medium-range missile launched by the North since it fired two in April 2014, says a South Korean defense official. Earlier this week, North Korea's state media said Kim had ordered tests soon of a nuclear warhead and ballistic missiles capable of carrying warheads. A military expert at the South's Konyang University says it's likely that Friday's launch was a test of a re-entry vehicle mounted on Pyongyang's purported Rodong missile. The North Korean missile fired may not be a Rodong but a long-range missile whose launch angle was altered so that it didn't fly its full range, says a professor at the Korea Advanced Institute of Science and Technology. He says the missile may have carried an empty warhead, which contains trigger devices but lacks plutonium or uranium, to see if it can survive the fiery re-entry and detonate at the right time. Japan denounced the launch and lodged a formal diplomatic protest, warning that it will take "all necessary measures" to defend itself, reports Reuters. (Pyongyang claims it could wipe out Manhattan.)