Spencer Stone: CCTV released of French train attack hero being 'repeatedly stabbed' on night out

He is reportedly in a stable condition in hospital after being stabbed four times in the chest

CCTV footage has been released of the knife attack on the American airman who overpowered a gunman on a Paris train in August.

Police are searching for two Asian men after Spencer Stone was stabbed "multiple times", CBS News reports, while on a night out with friends in Sacramento.

The attack was so brutal police reportedly treated the inident as a homicide when they arrived on the scene, International Business Times reports.

Mr Stone was reportedly attacked while defending a friend, an Air Force official told the BBC.

It is unclear if the CCTV footage shows the moment Mr Stone was stabbed.

He is in intensive care with a collapsed lung but is expected to survive, DailyMail.com reports.

The police sent out a tweet reporting that the incident is not related to terrorism. The tweet mentions that alcohol is believed to have been a factor in the attack.

They have also released footage of two suspects fleeing the area by car:

Spencer Stone was hailed as a hero after overpowering a gunman on a packed train in August.

Spencer Stone was also awarded the Airman's Medal for his role in disarming the gunman (EPA)

He was stabbed in the neck and eyebrow and nearly lost his thumb while wrestling the attacker, Ayoub El-Khazzani, to the floor.

Video from the aftermath of the attack showed Mr Stone ignoring blood pouring from his wounds as he tended to another passenger, who was bleeding from a gunshot wound.

He and two others, Alek Skarlatos and Anthony Sadler, were praised by French President Francois Hollande.

Mr Skarlatos tweeted: "Everybody send prayers out to the Stone family today."

No arrests have been made so far.