SACRAMENTO, Calif. — A California man pleaded guilty Friday to stabbing a U.S. airman who weeks earlier was hailed as a hero for helping thwart a terror attack aboard a French train.

James Tran, 29, faces a nine-year prison sentence after pleading guilty to attempted murder under a plea agreement, said Shelly Orio, a spokeswoman for the Sacramento County district attorney’s office.

He admitted knifing former Air Force Staff Sgt. Spencer Stone in October 2015 during a fight near a Sacramento bar.

Stone is one of three Sacramento men who tackled a gunman with ties to radical Islam on a Paris-bound passenger train in August 2015. Stone left the military last November as a staff sergeant assigned to Travis Air Force Base, said Staff Sgt. Scott Taylor, a spokesman at the base near Sacramento.

Tran pleaded guilty less than a week before he was to go on trial. He also pleaded guilty to enhancements including causing great bodily injury and using a deadly weapon, Orio said.

“I thought he got off kind of easy, but at the end of the day I’ve kind of moved on with my life,” Stone said by telephone. “We all make dumb decisions and we’ve got to pay for those decisions. I forgive the guy and hope he can grow from it…and kind of make it a positive thing in his life when he gets out.”

Tran is set for sentencing May 12.

Sacramento police have said Tran was the instigator in a confrontation that led to the stabbing.

Stone was with three women and another man when an argument with Tran’s group escalated into a fight that spread down a Sacramento street.

Police said Tran and his group did not know who Stone was until they saw news reports later.