French army Eiffel tower
The French army guard the Eiffel Tower in the wake of the Charlie Hebdo attacks Getty Images

The head of a decapitated man was found covered in Arabic script Friday morning (26 June) at a chemical gas company near Lyon, France, after a man rammed a vehicle into gas canisters, detonating them. An Islamist flag was found at the scene.

This is the fourth terrorism-linked attack in France in 2015.

A 35-year-old man, Yassin Salhi, has been arrested in connection with the attack at Air Products in Isère. Local police report that just before 10.00am a car drove recklessly into the business's parking lot.

Police reported employees witnessed a man being decapitated outside the business and that the attacker then rammed his vehicle into gas canisters causing an explosion that injured two workers.

Terror attacks in France

The terrorist attack is the fourth of 2015 in France, adding to the three that hit the country late in 2014.

In April, Algerian jihadist, Sid Ahmed Ghlam, 24, shot 33-year-old Aurelie Chatelain to death in a Paris suburb. Ghlam had plans to go on an extended shooting spree at two churches in the city, but shot himself in the leg in the 13th arrondissement and couldn't carry out his plan. He was found with Jihadi flags and literature.

In early February three anti-terrorism soldiers guarding a Jewish radio station in Nice were attacked and stabbed by Moussa Coulibaly, 31. Police were wary to call it a terrorist attack, however, because Coulibaly was "an unbalanced individual."

At the beginning of the year 20 people were killed and 22 injured in the attacks in Paris against satirical magazine Charlie Hebdo and a Jewish supermarket. Yemeni Sunni extremist group al-Queda in the Arabian Peninsula (AQAP) claimed responsibility for planning the attack.

Late in December 2014, 24 people were injured and one killed in a series of attacks that hit Joué-lès-Tours, Dijon, and Nantes. Two of the attacks, just a day apart, saw men drive into groups of pedestrians yelling "Allahu Akbar."

Prior to this spate of attacks, the most lethal act of terrorism was launched in 2012 by claimed al-Qaeda affiliate Mohammed Merah who went on a shooting spree over several days, killing seven people and wounding six.