SAINT-QUENTIN-FALLAVIER, France — A truck driver once under surveillance for radical Islamic ties crashed into an American-owned chemical warehouse in southeastern France on Friday and hung his employer’s severed head on a factory gate, along with banners with Arabic inscriptions.

The attack, which triggered an explosion that wounded two people, came on a day of violence that spanned three continents.

The suspect, who was apprehended soon after setting off the blast, is the latest French citizen implicated in extremist bloodshed in recent years after being flagged to authorities, then falling off the radar. Police were put on higher alert in the Lyon area after the assault, which revived fearful memories of attacks in January on a kosher market and satirical newspaper that left 20 dead.

“Islamist terrorism has again struck France,” Prime Minister Manuel Valls said.

The attack in France came on the same day that a gunman mowed down scores of European tourists on a beach in Tunisia and a suicide bomber killed more than two dozen worshippers at a Shiite mosque in Kuwait — violence that followed a call by Islamic State extremists to target “nonbelievers.”

No group immediately claimed responsibility for the factory attack in France. The severed head appeared to mimic the Islamic State group’s practice of beheading prisoners and displaying their heads for all to see, and came days after the militants urged attacks during the Muslim holy month of Ramadan.

Violent attacks in Tunisia, Kuwait and France

The bloodshed was condemned by the United Nations, the United States, Israel and others.

The French attack began about 9:30 a.m., when Yassine Salhi drove a utility truck to the gate of the Air Products factory in Saint-Quentin-Fallavier, southeast of Lyon, authorities said.

Prosecutor Francois Molins said Salhi was known to factory staff because he regularly made deliveries there, and they let him in the gate. Once beyond the sight of security cameras, Salhi plowed his truck into gas canisters in a factory warehouse, touching off an explosion, Molins said.

A knife and the decapitated body of Salhi’s employer were found at the site of the explosion, and the severed head was posted on a gate at the factory entrance with two flags bearing proclamations of Islamic faith, the prosecutor said.

Firefighters apprehended Salhi, and he was in custody Friday night along with his wife, sister and another person, while police sweeps of the vehicle and the suspect’s apartment were continuing, the prosecutor said.

Authorities described Salhi as a father of three who was married for more than 10 years, and who had been monitored for links to radical Islam from 2006-2008. “He continued to attract the attention of intelligence services from time to time from 2011 to 2014 for his links to the Salafist movement in the Lyon region,” Molins said.

Story compiled with information from The Associated Press.

Kamran Bokhari on a growing global threat

Acts of terror on three continents. For a more in depth look at a growing global threat. CCTV’s Mike Walter spoke to Kamran Bokhari, author and Political Islam in the Age of Democratization.

Follow Mike Walter on Twitter @mikewaltercctv

Paris on high alert after attack
In France – prosecutors say a delivery driver, with ties to radical Islam, cut off his boss’s head, hung it outside a chemical plant in southeastern France, and then tried to set the factory on fire.
CCTV’s Kate Parkinson filed this report.