UPDATE: Early accounts claiming that the three heroes were U.S. Marines were incorrect. They were instead a U.S. National Guardsman, a U.S. Airman, and a college student. The three are childhood friends.

You can read about their story and the latest information we have on the thwarted attack here.

U.S. Marines heard the distinctive sound of a gunman charging an AKM-pattern rifle in the bathroom of a high-speed Amsterdam-to-Paris train, and beat him down before he could carry out a massacre:

A crazed gunman, who opened fire with an assault rifle onboard a high-speed train was detained by a group of US Marines who were travelling on the service.

The man is understood to have been overheard loading the Kalashnikov AK-47 assault rifle in the toilet by the un-armed Marines.

Three people were injured when the man opened fire, but he was soon forced to the ground and detained.

A French actor, and American, and a Briton were injured before the Marines took him to the ground, disarmed him, and held him for French authorities near the town of Arras in northern France.

The single photo of the gunman shown so far suggests that he’s a little worse for wear after his encounter with the Marines.

Attitude goes a long way towards determining the winner of a fight. In this instance, the honed reflexes and warrior spirit of the Marines enabled them to quickly overcome what is believed to be a fully-automatic weapon and subdue the gunman with a minimal number of casualties, preventing a possible massacre.

This is a breaking story. We will update it as more information becomes available.

UPDATE: One of the three Marines that subdued the gunman—now confirmed as a known Moroccan Islamist—was shot in the struggle. Accounts of the severity of the Marine’s injuries range from critical to “run some dirt on it” depending on the media outlet.

The terrorist had at least nine full magazines (270 rounds) of ammunition for his full-auto AKM, and was also apparently armed with a pistol and a knife.

It is no exaggeration at all to make the assumption that if it wasn’t for the actions of these three U.S. Marines that there would have been dozens of casualties in what appears to be yet another “lone wolf” Islamic terrorist attack.