By Catherine Lagrange
SAINT-QUENTIN FALLAVIER, France (Reuters) - A decapitated body daubed with Arabic writing was found at a U.S. gas company in southeast France on Friday after an assailant rammed a car into the premises, triggering an explosion, in a suspected Islamist militant attack.
The attacker survived the blast and was arrested. The identity of the beheaded victim was not clear but a police source said it was a manager of a transport company, on the site for a delivery. It was not yet clear whether his vehicle was then used by the attacker to gain entrance.
Speaking from a European Union summit in Brussels, French President Francois Hollande described it as a terrorist attack and said all measures would be taken to stop any future strikes on a country still reeling from Islamist assaults in January.
Interior Minister Bernard Cazeneuve said one suspect, named as Yassin Sahli, had been arrested, and police were holding other suspected accomplices. 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 Islamists.
"A person was killed and decapitated and the anti-terrorist section of the Paris prosecutor has been immediately deployed," Cazeneuve said at the scene of the attack in an industrial zone by the town of Saint-Quentin Fallavier, 30 km (20 miles) southeast of Lyon.
French media said Sahli was a 35-year-old professional driver who lived in the Lyon suburbs. There was no official confirmation of that but 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 2:00, 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."
It was not known whether the victim, so far the only known fatality in the incident that also injured two people, was decapitated before or after the car smashed into the building.
"We all remember what has happened in our country, and not just in our country. So there is plenty of emotion. But emotion cannot be the only response - that must be action, prevention and dissuasion," Hollande said.
Saint-Quentin Fallavier, with its good air, rail and road links, is one of Europe's major logistics hubs, venue to some 1.5 million square meters (370 acres) of depots, with through-traffic of 5,000 trucks a day.
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.
At least 27 people were killed on Friday in a gun attack on a beachside hotel in Tunisia. In Kuwait, Islamic State claimed responsibility for a suicide bombing that killed more than 10 people at a packed Shi'ite mosque.
ISLAMIST FLAG
Police sources earlier said the decapitated body was found at the site, along with a flag bearing Islamist inscriptions.
Local newspaper Le Dauphine said the head, covered in Arabic writing, was found hanging from a fence.
France, which has deployed 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, Valls has said repeatedly that France has never seen a higher threat level.
The site belonged to Air Products, a U.S. industrial gases and chemicals company, according to a spokeswoman for Air Liquide, a French company in the same sector. 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".
The chairman and CEO of Air Products 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.
No group claimed responsibility for the attack and the motive was unknown.
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.
Jean-Paul Bonnetain, prefect of the local Isere region, said the vehicle used to gain access to the site had the necessary authorization to do so.
Cazeneuve said the government had ordered security to be stepped up around all sensitive sites.
(Reporting by Paris bureau; writing by Mark John; editing by Mark Trevelyan)