Update as of 7:08 a.m. EDT: Officials say the gunman who allegedly opened fire on a French train Friday is suspected of belonging to a radical Islamist group, though his identity has not been established.

French Interior Minister Bernard Cazeneuve said: "If the identity he has given is confirmed, he is a 26-year-old Moroccan who lived in Spain in 2014 and in Belgium in 2015. The investigation opened in Belgium should establish very precisely the path taken by this terrorist," the Telegraph reported.

In addition, Reuters reported that the gunman had been identified as dangerous by foreign security services and had been under police surveillance, a French source with knowledge of the case said.

A Spanish official told the Associated Press that he had also traveled to Syria.

Original story:

France's interior minister has praised the “great bravery” of the American passengers who helped overpower a man after the latter opened fire aboard a French train Friday. One of the men involved in subduing the gunman said there would have been "real carnage" had they not intervened.

The incident took place around 6 p.m., local time, (12 p.m. EDT), aboard a high-speed train traveling from Amsterdam to Paris. The attacker, who media reports have identified as 26-year-old of Moroccan origin, was known to France's intelligence services and was reportedly overheard by the Americans while loading his weapon in the train's toilet cubicle.

The three Americans were identified by media reports as Sacramento State University senior Anthony Sadler, soldier Alek Skarlatos of Roseburg, Oregon, and Spencer Stone, a member of the U.S. Air Force who was injured during the incident. A British passenger, who Reuters named as Chris Norman, also assisted in subduing the attacker.

"My friend Alek (Skarlatos) yells, 'Get him,' so my friend Spencer [Stone] immediately gets up to charge the guy, followed by Alek, then myself," Sadler said in an interview with CNN.

"The three of us beat up the guy," he said. "In the process Spencer gets slashed multiple times by [the gunman's] box cutter, and Alek takes the AK away.

"I begin to tie him up with help from Chris, another passenger. I notice a man had his throat cut at which Spencer begins to apply pressure to the neck wound before he bled out."

Norman told Reuters that he felt “relief that nobody actually got killed. ... It could have been a real carnage and there's no question about that."

Passengers spoke of hearing gunshots as the train was traveling through the Belgian countryside, where the attack took place, and of seeing bloodied individuals rolling out into the grass when the train came to a stop during a chaotic few minutes of shooting, the New York Times reported. The attacker reportedly had several weapons on his person and in his luggage, including an assault rifle, a pistol and several bladed weapons.

French Interior Minister Bernard Cazeneuve told reporters: “Together with the president and prime minister, I want to express to these two American passengers, who were particularly courageous and showed great bravery in very difficult circumstances all our gratitude, recognition and admiration.

“Without their composure we could have been confronted with a terrible incident," he added.

Cazeneuve was reluctant to characterize the incident as a terrorist attack, although French prosecutors said an inquiry was being launched by counterterrorism investigators, the Guardian reported. Belgian Prime Minister Charles Michel tweeted his condemnation of what he called the "terrorist attack."

France has been on high alert this year, after suffering a series of high-profile terrorist attacks beginning with the murder of several members of the staff of satirical magazine Charlie Hebdo in January.