A gunman opened fire on board a train traveling from Amsterdam to Paris Friday, wounding three people before being overpowered by passengers including two American servicemen.
French officials say the gunman's motives are not known, but say anti-terrorism police are leading the investigation. Police have identified the man as a 26-year-old of Moroccan origin and say he was armed with an AK-47 assault rifle, a handgun, and a box cutter or other blade.
French Interior Minister Bernard Cazeneuve said the suspect was arrested at a railway station in the northern French town of Arras, where the train was sent after being rerouted.
Cazeneuve told a news conference Friday that two U.S. citizens helped to disarm the attacker and that one of them was among the injured. "Without their courage, we would have surely faced a terrible tragedy," he said.
Anthony Sadler, a U.S. student, said he and two of his friends in the U.S. military were able to subdue the attacker and help others who had been wounded.
"I'm just a college student, it's my last year in college, I came to see my friends on my first trip in Europe and we stopped a terrorist, it's kind of crazy," Sadler told reporters.
White House reaction
In Washington, a White House official confirmed that U.S. service members were among those who overpowered the attacker and said two Americans were injured.
"The president expressed his profound gratitude for the courage and quick thinking of several passengers, including U.S. service members, who selflessly subdued the attacker," the official said.
French media reports say the American men were U.S. Marines. U.S. military officials, however, confirmed only that an American soldier had been wounded but said the injuries were not life-threatening.
The attack took place while the high-speed train, operated by Thalys, was traveling through Belgium with 554 people on board.
Belgian Prime Minister Charles Michel condemned what he called "the terrorist attack" and said he and French President Francois Hollande are working closely on the investigation.
Thalys is partly owned by the French and Belgian railways.
French authorities have been on high alert since Islamic militants killed 17 people in and around Paris in January.