PARIS — At least one man attacked a gas factory on Friday in southeastern France, posting a severed head at the factory's entrance along with banners covered with Arabic writing, officials said. France immediately opened a terrorism investigation.
The attack was perpetrated by one or two people and France has stepped up the protection of its chemical sites, President Francois Hollande said at a news conference in Brussels.
“The attack is terrorist in nature when you have a decapitated body with inscriptions,” Hollande said.
One person had been arrested, identified and is being questioned, he said.
Just before 10am, a car driven by one man, who may have been accompanied by another person, entered the Air Products & Chemicals Inc plant at high speed, ramming into gas containers.
“There’s no doubt that the intention was to cause an explosion,” Hollande said.
A security official said a severed head was found posted on the gate at the entrance to the factory, in what appeared to be an echo of Islamic State's practice of beheading prisoners and displaying the heads for all to see.
Two flags, one white and one black, both with Arabic inscriptions, were found nearby, the security official said.
Interior Minister Bernard Cazeneuve said the man arrested in the attack was known to intelligence services for possible ties to Islamic extremists but had no arrest record.
He said the investigation had just begun and cautioned against jumping to conclusions.
The suspect had been flagged as an extremist in 2006 but police monitoring dropped off two years later, the minister said.
The attack comes after 17 people were killed at a satirical magazine and a kosher grocery in Paris in January by a radicalized trio, catapulting France’s capital onto the front pages of newspapers around the world.
The French government mobilised 10,000 soldiers to guard vulnerable sites around the country.
The factory that was attacked is a subsidiary of the US company Air Products, based in Allentown, Pennsylvania. Situated in an industrial zone outside the French town of Saint-Quentin-Fallavier, it gas used by industry and hospitals, according to a website dedicated to local industries.
In addition to the factory, the company has a customer services centre in Aubervilliers outside Paris.