Eddie Ray Routh was arraigned early Sunday in the deaths Saturday of Mr. Kyle, who wrote the best-selling book American Sniper: The Autobiography of the Most Lethal Sniper in U.S. Military History, and Chad Littlefield, 35.
They were killed at a shooting range at Rough Creek Lodge, about 50 miles southwest of Fort Worth.
Travis Cox, the director of a nonprofit organization that Mr. Kyle helped found, said Sunday that Mr. Kyle, 38, and Mr. Littlefield had taken Routh to the range to try to help him.
Mr. Littlefield was Mr. Kyle’s neighbor and “workout buddy,” Mr. Cox said.
“What I know is Chris and a gentleman — great guy, I knew him well, Chad Littlefield — took a veteran out shooting who was struggling with PTSD to try to assist him, try to help him, try to, you know, give him a helping hand, and he turned the gun on both of them, killing them,” Mr. Cox said.
Mr. Kyle’s nonprofit, FITCO Cares, provides at-home fitness equipment for emotionally and physically wounded veterans.
“Chris was literally the type of guy, if you were a veteran and needed help, he’d help you,” said Mr. Cox, the director of FITCO Cares.
Capt. Jason Upshaw with the Erath County Sheriff’s Office said Routh had not made any comments that might indicate a motive.
Sheriff Bryant didn’t know whether Routh was on medication or had been diagnosed with post-traumatic stress disorder.
Routh was being held on one charge of capital murder and two charges of murder.
Captain Upshaw said Routh used a semi-automatic handgun, which authorities later found at his home.
Captain Upshaw said ballistics tests weren’t complete Sunday, but authorities believe it was the gun used in the shootings.
The U.S. military confirmed Sunday that Routh was a corporal in the Marines, serving in active duty from 2006 to 2010.
He was deployed to Iraq in 2007 and Haiti in 2010.
His current duty status is listed as reserve.
Routh is being held on $3 million bond.
Mr. Kyle’s best-seller detailed his 150-plus kills of insurgents from 1999 to 2009.
Mr. Kyle said he killed 160 people, perhaps many more, making him one of the leading U.S. military snipers of all time.
In the course of four combat deployments to Iraq, he said insurgents nicknamed him “the devil of Ramadi” and placed a $20,000 bounty on his head.
“After the first kill, the others come easy,” Mr. Kyle wrote.
“I don’t have to psych myself up, or do something special mentally — I look through the scope, get my target in the cross hairs, and kill my enemy, before he kills one of my people.”
Mr. Kyle, former Texas ranch hand and bronco buster who called himself the antithesis of the “refined assassin,” joined the SEALs in 1999.
He served four combat deployments before retiring in 2009.
Mr. Kyle’s steady nerve, his patience for stalking, and his pinpoint marksmanship through his rifle scope earned him two Silver Stars and five Bronze Stars.
His book sold hundreds of thousands of copies.
With his Texas drawl, hulking physique, and tightly reserved public manner, Mr. Kyle drew a degree of celebrity in the past year as he appeared on late-night talk shows and in the NBC competition show Stars Earn Stripes, which pairs military and law enforcement veterans with actors in drill exercises.
Sheriff Bryant said the three men went to the shooting range about 3:15 p.m. Saturday.
A hunting guide at Rough Creek Lodge came across the bodies of Mr. Kyle and Mr. Littlefield about 5 p.m. and called 911.
Captain Upshaw said autopsies were pending and he could not say how many times the men were shot.
After the shootings, Routh left the range in Mr. Kyle’s pickup, Sheriff Bryant said, first going to his sister’s home where he told her and her husband what he had done.
Routh left, Sheriff Bryant said, and the couple called local police.
Routh arrived at his home in Lancaster, about 17 miles southeast of Dallas, at about 8 p.m.
Police arrested him after a brief pursuit.