By Ralph Ellis and Paul Cruickshank
(CNN) — A massacre on a high-speed train in France was prevented Friday when two U.S. Marines in civilian clothing surprised an Islamist militant who was loading his automatic Kalashnikov rifle, a senior European counterterrorism official told CNN.
The gunman fired on the Marines with a handgun, the official said, wounding at least one of them. Authorities said three people were injured aboard the Thalys train traveling from Amsterdam to Paris.
The Marines overpowered the suspect, who was placed under arrest when the train was rerouted to the town of Arras, about 115 miles (185 kilometers) north of Paris.
The gunman, a Moroccan national, was on the radar screen of European counterterrorism agencies for his radical jihadist views, the official said.
A second security source told CNN the gunman was known by French intelligence. The official said it appeared the gunman was sympathetic to ISIS, but a full determination on his specific loyalties had yet to be reached.
The man had plenty of ammunition, the first official said, and the Marines prevented a massacre.
The attack has not officially been classified as an act of terrorism, although the senior European counterterrorism official indicated it was.
Calling the attack “an attack of barbaric violence,” Interior Minister Bernard Cazeneuve said the anti-terrorism prosecutor’s office in Paris will investigate.
He expressed “gratitude and admiration” for the Marines help.
Two people were hospitalized with serious injuries but their lives are not in danger, said Anthony Blondeau, spokesman for the city of Arras.
He said one of them was an American, but did not specify that he was one of the Marines. It’s unknown whether the second Marine was wounded.
The third person injured was French actor Jean-Hugues Anglade, who has a light hand injury, Blondeau said.
Christophe Piednoel, spokesman from the French railway company SNCF, said the suspect carried an automatic weapon and a bladed weapon.
France has been the site of several lone-wolf terror attacks this year, including the killing of 17 people in Paris in attacks on a satiric magazine and a kosher store.
CNN’s Pierre Meilhan contributed to this report.