"American Sniper" author and ex-Navy SEAL Chris Kyle was fatally shot at gun range in Glen Rose, Texas, Saturday. A second man, Chad Littlefield, was also gunned down.  

According to the New York Times, a Texas man, Eddie Ray Routh, 25, has been arrested in the crime. 

Local TV station WFAA-TV reported that Kyle was killed "while helping another soldier who was recovering from post-traumatic stress syndrome." Sources told the news outlet that Kyle and Littlefield were attempting to help Routh cope with his PTSD when he opened fire.  

The killing occurred at the Rough Creek Lodge in Earth County. The lifeless bodies of Kyle, 38, and Littlefield, 36, were discovered at the scene.  

According to police reports, Routh shot the men around 3:30 p.m. and fled the scene in a Ford pickup. He was arrested at his home in Lancaster. He was arraigned later Saturday and is charged with two counts of capital murder. 

Kyle wrote the 2012 bestseller "American Sniper: The Autobiography of the Most Lethal Sniper in U.S. Military History," which chronicled his time as a marksman from 1999 to 2009, including service in the Iraq War, where he is said to have shot 150 insurgents. According to NBC, as a member of Navy SEAL Team 3, Kyle earned the nickname the "Devil of Ramadi," and insurgents placed a $80,000 bounty on his head.  

The legendary sniper was decorated with two Silver Stars, two Navy Achievement Medals and five Bronze Stars. 

Kyle's post-military career included his involvement with the FITCO Cares Foundation, which assists wounded and PTSD veterans. 

FITCO has posted a statement honoring Kyle. 

"The FITCO Cares Foundation will always carry the torch to help our brave men and women who have survived combat but are still fighting to survive post traumatic stress disorder. Chris Kyle helped establish this foundation, and we are committed to make sure his memory lives on forever." 

Please pray for all those who loved Chris. He will be forever missed."

Kyle is survived by his wife and two children.