SAINT-QUENTIN FALLAVIER, France A delivery man with known Islamist connections beheaded his boss and left the body, daubed with Arabic writing, at the site of a U.S.-owned gas factory in southeast France before trying to blow up the complex. 
 
 The assailant rammed his delivery van into a warehouse containing gas canisters, triggering an initial explosion, and was arrested minutes later as he tried to open canisters containing flammable chemicals, prosecutors said on Friday. 
 
 Police found the head of the victim, the 54-year-old manager of the transport firm that employed the suspect, dangling from a fence. 
 
 "The head was discovered hanging on the factory's wire fence, framed by two flags that included references to the shahada, or (Muslim) profession of faith," Paris public prosecutor Francois Molins told a news conference. 
 
 France is still coming to terms with attacks by Islamist gunmen who killed 17 people in January at a satirical weekly newspaper and a Jewish food store. 
 
 The latest attack occurred on the same day that a gunman killed at least 37 people at a Tunisian beachside hotel and an Islamic State suicide bomber killed two dozen and wounded more than 200 at a mosque in Kuwait. 
 
 "There is no other link other than to say that terrorism is our common enemy," said President Francois Hollande, returning to Paris from an EU summit in Brussels. 
 
 "There should be no doubt as to our country's ability to protect itself and remain vigilant," he said, announcing a tightening of national security to levels he said were unprecedented in recent decades. 
 
 Hollande said there were inscriptions on the headless body, and police sources said they were in Arabic, but officials did not reveal their content. 
 
 FATHER OF THREE 
 
 No group claimed responsibility for the French attack and the motive was unknown. 
 
 The attacker was injured in the blast and arrested on the site. His wife, sister and a third person were taken into custody for questioning. 
 
 Interior Minister Bernard Cazeneuve named the suspect as Yassin Sahli. He said Sahli did not have a criminal record but had been under surveillance from 2006 to 2008 on suspicion of having become radicalized by Islamist associates. 
 
 The attack occurred at an industrial zone near the town of Saint-Quentin Fallavier to the south of the city of Lyon. Its air, rail and road links have made it one of Europe's major logistics hubs, with through-traffic of 5,000 trucks a day. 
 
 Sources close to the investigation said Sahli was a 35-year-old professional driver who lived in the Lyon suburbs. Europe 1 radio interviewed a woman they identified as his wife. 
 
 "In the morning he left for work and didn’t come home between noon and 2. I was waiting for him," she told Europe 1 radio, saying she and her family of three children lived normal lives as Muslims. "My heart is about to give out." 
 
 French television filming outside Sahli's apartment showed pictures of police leading out a woman, her head covered by a blanket, into a waiting car. Forensic police were carrying out searches on the ground-floor apartment. 
 
 "They are a very normal family," a neighbor who gave her name as Brigitte said. "I only talked with madame, he didn't say hello or goodbye," the 46-year-old housewife told Reuters. 
 
 Police questioned employees for several hours at the transport company run by the victim and seized the suspect's car. A cleaner at a neighboring business described the victim of the attack as a friendly and polite man, "always saying good morning or good evening and have a nice weekend to his staff". 
 
 UNPRECEDENTED THREAT 
 
 The attack underlined again the difficulty for authorities across Europe and elsewhere of protecting so-called "soft" targets against strikes by assailants operating by themselves or in small undercover cells. 
 
 France, which has contributed aircraft to the international coalition fighting Islamic State insurgents in Iraq, has long been named on Islamist sites as a primary target for attacks. 
 
 In January, Islamist gunmen killed 17 people in the offices of the Charlie Hebdo satirical weekly and a Jewish food store. 
 
 In April, Prime Minister Manuel Valls said no fewer than five attacks had been thwarted in the country since then. 
 
 Noting that hundreds of French nationals are in Syria where they risked being radicalized by Islamist fighters, officials have long said France has never seen a higher threat level. 
 
 The site of Friday's attack belonged to Air Products, a U.S. industrial gases and chemicals company. It was immediately ringfenced by police and emergency services. 
 
 Air Products said its crisis and emergency response teams were "working closely with all relevant authorities" and that it had increased security at its installations around the world. 
 
 The company's chairman and chief executive is Seifi Ghasemi, who in 2011 testimony to a U.S. Senate committee described himself as Iranian-born. Mainly Shi'ite Iran is a sworn enemy of Sunni-dominated Islamic State. 
 
 According to French regulations applicable to zones where gases and chemicals are handled, the site would have been required to implement security arrangements at the low end of the European Union's so-called "Seveso" scale, named after the location of an industrial accident in northern Italy in 1976. 
 
 Prosecutor Molins said closed-circuit TV images showed the attacker arriving at the site. Because his vehicle was authorized to make deliveries, it was allowed through the gates. 
 
 The CCTV cameras lost track of his movements for several minutes, then picked up the van again as it accelerated toward a warehouse within the premises. A loud explosion was heard. 
 
 When emergency services arrived a few minutes later, they found the headless body of the victim by the van and a knife nearby. They overpowered the suspect as he was opening bottles of acetone, a flammable liquid chemical. 
 
 Cazeneuve said the government had ordered security to be stepped up around all sensitive sites and Hollande announced that security arrangements in the region would be placed at their highest level for the next three days. 
 
 (Reporting by Paris bureau; writing by Mark John; editing by Mark Trevelyan, Larry King) ||||| Suspect named as Yassin Sahli arrested after man seemingly tried to blow up factory by crashing a vehicle into warehouse containing gas canisters 
 
 France has raised its security alert to the highest level after police discovered a decapitated body and flags with Arabic inscriptions following an attack in which a man seemingly tried to blow up a factory belonging to a US gas company. 
 
 A suspect arrested at the scene at Saint-Quentin-Fallavier, near Lyon in south-west France, was named by the French prosecutor as 35-year-old Yassin Salhi, an employee at a transport company run by the victim. The suspect was known to people at the Air Products factory because he came in regularly for deliveries, the prosecutor said. 
 
 Terrorist attacks in Tunisia, Kuwait and France stun three continents Read more 
 
 The victim’s head was found hanging on a fence next to two inscribed flags, with the rest of his body inside the factory. 
 
 “It is a terror attack. There is no doubt about it,” the French president, François Hollande, told reporters in Brussels before leaving a European council summit to return to Paris. France’s interior minister, Bernard Cazeneuve, said Sahli had previously faced investigation over radicalisation, although he had no police record. The prosecutor said that between 2011 and 2014, French security services had been investigating Salhi for connections to salafist groups in the Lyon area. 
 
 
 
 It remained unclear whether any Islamist motivation for the attack might be mixed with personal grudges. There is no evidence it was coordinated or connected with the Tunisian beach shootings or a suicide bombing at a Kuwaiti mosque during Friday prayers. 
 
 Facebook Twitter Pinterest France will not give in to fear, says French president François Hollande 
 
 Hollande led a security meeting at the Elysée palace, saying afterwards he had raised the security alert in the south-east region to maximum. A priority, he added, was to determine if the alleged attacker had accomplices. 
 
 The suspect’s wife was later arrested, as was his sister and an unidentified man reportedly seen driving past the Air Products site several times before the attack. Earlier, a woman identifying herself as Sahli’s wife told Europe 1 radio that she and the couple’s three children had known nothing of the planned attack. “My heart is about to give out,” she said. 
 
 The suspect was believed to have hung his manager’s head on a fence before driving a vehicle into a warehouse filled with gas canisters, causing an explosion, a local newspaper, Dauphiné Libéré, said. Two people were hurt in the blast. 
 
 Security officials told Associated Press the attacker had seemingly hoped to cause a far bigger explosion with his actions, believing the canisters were more combustible than they proved. Hollande said the apparent intention of the attack had been to blow up the factory. 
 
 Gérard Larcher, the centre-right president of the French Sénat, the upper house of parliament, arrived at the scene on Friday afternoon, saying he had spoken to the local public prosecutor and members of France’s anti-terrorist brigade in Paris. 
 
 He said the attacker was known at the gas storage unit where he made deliveries. “This is why he had access to the site,” Larcher said. “There is a very strong sense of shock,” he added. Larcher paid tribute to a firefighter who reportedly stopped the attacker blowing up a stock of gas bottles. 
 
 Facebook Twitter Pinterest Video: French suspect had been under surveillance, says minister 
 
 Mehdi, a 23-year-old Muslim man who lives 100 metres from the depot, said he was furious that “these people claim to be Muslims”. 
 
 “I am a young Muslim,” he said. “I am keeping Ramadan right now. It is Friday. To carry out this attack on a Friday during the holy month is not respectful of Islam. These people may call themselves Muslims but they are not. I say to them, you do not have the right to cut off someone’s head, you do not have the right to explode anything near our homes where our children live. 
 
 “We have French, Turks, Arabs, Chinese, Cambodians living around here. There is no more tension than anywhere else,” Mehdi said, adding that he feared the attack would bring reprisals against the Muslim community in France. 
 
 Air Products confirmed there had been an incident at its factory and said all staff had been evacuated. 
 
 “We can confirm that an incident occurred at our facility in L’Isle-d’Abeau, France this morning,” a statement said. “Our priority at this stage is to take care of our employees, who have been evacuated from the site and all accounted for. Emergency services are on site and have contained the situation. The site is secure. Our crisis and emergency response teams have been activated and are working closely with all relevant authorities.” 
 
 France has been on alert for possible Islamist-related attacks since gunmen killed 17 people in January in assaults on the offices of the Charlie Hebdo satirical magazine and a Jewish food store. 
 
 Hollande said the response to such attacks should be measured. He said: “We all remember what has happened in our country, and in other countries. There is a lot of emotion, but emotion is not the only answer. We need action, deterrence, and we need to spread our values and to never give in to fear.” 
 
 Air Products, based in Pennsylvania, supplies gases, chemicals and associated equipment. It has 20,000 employees and outlets in 50 countries.
– Yesterday's attack on a gas plant in Saint-Quentin-Fallavier, France, was made all the more gruesome by the revelation that a severed head was found hanging from the factory's wire fence along with banners with Arabic inscriptions. That head belonged to the alleged attacker's boss, reports Reuters. French officials have named the suspect, who is in custody, as Yassin Sahli; he is a 35-year-old delivery driver, and police say the head found on the fence was that of his 54-year-old boss. The Guardian reports the remainder of the man's body was discovered inside the factory. Reuters reports that the delivery van had the authorization to enter the site, and prosecutors say Sahli made regular deliveries to the US-owned Air Products factory. After the van passed through the main gates it was filmed speeding up as it barreled toward the warehouse. Sahli was "overpowered" as he tried to open canisters containing a flammable liquid, per Reuters. No one has claimed responsibility for the attack, and as the Guardian puts it, "It remained unclear whether any Islamist motivation for the attack might be mixed with personal grudges."