GRETNA, La. >> The man accused of fatally shooting former NFL player Joe McKnight acted in self-defense because McKnight was threatening him and trying to climb into his car, his lawyers say.

Ronald Gasser, 55, of Terrytown, had initially been arrested on a manslaughter charge but was indicted Wednesday on a charge of second-degree murder, which carries a mandatory life sentence if he’s convicted. He’s being held on $750,000 bond.

“Information provided from our sources indicates that McKnight exited his vehicle and attempted to enter through the passenger window of Mr. Gasser’s vehicle while threatening him with serious bodily harm,” attorneys Matthew Goetz and Gerard Archer said in an email sent after-hours Thursday to The Associated Press.

They did not further describe the sources and Goetz did not immediately return a phone call today.

The email added that while the attorneys don’t yet have forensics evidence, they believe McKnight’s wounds, and shell casings found in Gasser’s car, will be consistent with the sources’ account.

“Mr. Gasser did what he is legally entitled to do and defended himself. … Mr. Gasser did not know Mr. McKnight nor was this in any way racially motivated. He feared for his safety and acted,” said the email, sent by Goetz and signed by both lawyers.

Authorities have said both the 28-year-old McKnight, who was black, and Gasser, who is white, were driving erratically and yelling at each other on the bridge from the main part of New Orleans to its west bank neighborhood before they stopped.

“It is our understanding (which can be verified by a simple viewing of the photos of the scene following the incident) that Mr. McKnight drove his vehicle from several car lengths behind Mr. Gasser and then pulled over onto the shoulder of the road trapping Mr. Gasser’s vehicle,” the attorneys’ email said.

After the shooting, Gasser “did what is expected of people who are following the law,” they wrote. “He waited for the police and cooperated fully with the investigation.”

A second-degree murder charge can be brought against someone who means “to kill or to inflict great bodily harm.”

Asked Thursday whether McKnight had reached into Gasser’s car, Jefferson Parish Sheriff Newell Normand said, “I’m not here to compromise our case and I’m not here to argue our case. The district attorney … alone will decide when he wants to reveal certain aspects of this case.”

Gasser was released after initial questioning, but was re-arrested Dec. 6 and jailed on a charge of manslaughter.

The sheriff was criticized for not keeping Gasser in jail from the start, even though Gasser was immediately identified as the shooter. Normand said at the time that a thorough investigation was needed because of laws that provide a defense to certain crimes. He did not elaborate.

McKnight was considered the No. 1 running back recruit in the country when he came out of John Curtis Christian School in Louisiana in 2006. He signed with the University of Southern California, where he ran for 2,213 yards and 13 touchdowns and caught 66 passes for 542 yards and two scores in three seasons.

In the NFL, he played three seasons for the New York Jets and one with the Kansas City Chiefs. He spent the past season in the Canadian Football League, playing two games for the Edmonton Eskimos and three for the Saskatchewan Roughriders.