CNN) -- A former Navy SEAL who said his 150-plus sniper kills prompted Iraqi insurgents to place a bounty on his head was fatally shot at a Texas gun range, authorities said.
Chris Kyle, 38, was one of two men killed Saturday afternoon in Glen Rose, southwest of Fort Worth, the Texas Department of Public Safety said. Chad Littlefield, 35, was also shot to death.
Police arrested suspect Eddie Ray Routh, 25, after a brief pursuit and arraigned him on two counts of capital murder, according to the safety agency.
Kyle was a major advocate for war veterans and worked to ensure their needs were met.
"He was a man of incredible character, he led by example," said Jason Kos, Kyle's friend told CNN. "He always stopped to take time to talk to whoever was around him. Just incredibly humble, very funny as well."
He helped establish nonprofit Fitco Cares Foundation to enable veterans battling post-traumatic stress syndrome get access to exercise equipment..
In a statement, the foundation described Kyle as an "American hero," and pledged to carry on his mission.
Kyle served in four combat tours in Iraq, and received two Silver Stars, among other commendations.
He left the Navy in 2009, and later recounted his days as a sniper in "American Sniper," a New York Times best seller.
In the book, Kyle describes how Iraqi insurgents nicknamed him "the devil" and placed a bounty on his head.
He purports to have more than 150 sniper kills. According to the book, the Pentagon confirmed those kills, which Kyle described as a record number for any American.
During an interview with Time magazine last year, Kyle defended his decision to write the book despite the secretive nature of the SEAL world.
"It's kind of frowned on," he told the magazine. "But I'm not trying to glorify myself. I didn't want to put the number of kills I had in there. I wanted to get it out about the sacrifices military families have to make."
He said though killing did not come easy at first, he knew it meant saving a life.
"The first time, you're not even sure you can do it," he said in the interview. "But I'm not over there looking at these people as people. I'm not wondering if he has a family. I'm just trying to keep my guys safe. Every time I kill someone, he can't plant an IED. You don't think twice about it."
Before becoming a sniper, Kyle was a Texas rodeo cowboy. He started shooting as a child during hunting trips with his father.
After leaving the Navy four years ago, he founded Craft International, a military training company.
In addition to working with the SEALs, he also served with units in the Army and Marines, according to a bio on his company website.
His combat experience includes close-quarters battle, desert patrols and training foreign allies, it says.
Kyle also appeared on the NBC reality show "Stars Earn Stripes" that lets competitors take on missions that are based on actual military exercises.
