At least one person has been killed and two injured in an attack on an industrial-gas factory in Saint-Quentin-Fallavier, in the French southeastern department of Isere, said French President Francois Hollande Friday.

Reports say the attacker forced his way to the factory at around 10.00 a.m. local time (0800GMT) with a car causing an explosion.

Hollande, who is in Brussels for an EU summit, confirmed the attack was “of a terrorist nature”.

“The attacker drove into the gas canisters without a doubt to provoke an explosion,” Hollande said. “One person was driving the car and was perhaps accompanied by another.”

He said a suspect had been arrested and had been identified. Sensitive sites near the location of the attack have had their security reinforced, he added.

Hollande also confirmed earlier police reports saying a victim had been decapitated.

French newspaper Le Figaro had reported earlier that decapitated head of a victim had been found hanging on the fence of the company grounds. Hollande said the head had inscriptions on it. The victim has not yet been identified.

The French president is due to come back to France in the afternoon and he will hold an emergency defense meeting at 3.00 p.m. (1300GMT).

Speaking onsite, French Interior Minister Bernard Cazeneuve said the suspected attacker had been identified as Yassin Salhi, known to French intelligence services due to alleged links with Salafist movement.

According to Cazeneuve, the attacker had “no criminal record” but had been flagged in 2006 as “possibly radicalized”. The file was not “renewed in 2008”. He “was not identified as a risk,” said Cazeneuve.

He added “others who may have been involved” were taken into custody.

France’s Prime Minister Manual Valls, who is in Colombia for an official visit, has demanded to tighten security measures on sensitive sites in response to the attack.

The Paris anti-terrorist prosecutor has launched an investigation into the attack, according to a statement from the capital’s High Court.

France has been on high alert since January 2015 following two deadly attacks against French satirical magazine Charlie Hebdo headquarters and a Kosher store, leaving 17 people dead (Anadolu Agency)