A US airman who foiled a terrorist attack on a train in Belgium in August has been stabbed while protecting a friend.
Spencer Stone, 25, was in a stable condition in hospital after the incident which happened in Sacramento, California at 12.45am.
Officials said he was stabbed at a bar near Travis Air Force Base where he is stationed.
Stone was reportedly stabbed four times in the chest. According to one report he was stabbed in the heart and lung.
A police spokesman in Sacramento said: "It is believed that the victim was out with a group of friends when a physical altercation led to the victim being stabbed multiple times in his upper body.
In a statement the the US Air Force said: "He is alive and in stable condition at this time. We do not have any information as to the events preceding the incident."
An Air Force spokesman added: "He has been transported to a local hospital and is currently being treated for injury. The incident is currently under investigation by local law enforcement."
According to a local television station the victim suffered "multiple stab wounds to the torso".
Update: The assault incident is not related to a terrorist act. Assault occurred near a bar, alcohol is believed to be a factor.
Police initially did not think he would survive and began treating the incident as a murder investigation, but his condition improved in hospital.
No-one has been arrested in connection with the stabbing.
Stone and two friends, Alek Skarlatos and Anthony Sadler, were hailed as heroes after they they tackled and disarmed a gunman on board a train from Amsterdam to Paris.
They reacted after Ayoub El-Khazzani, 26, burst into a train carriage firing a Kalashnikov.
Mr Stone charged El-Khazzani and was injured in the struggle, later having to undergo surgery to reattach part of his hand.
Alek Skarlatos, said on Twitter: "Everybody send prayers out to the Stone family today."