Former Navy SEAL, Chris Kyle, was one of two men killed in a shooting on a Texas gun range on Saturday.

Kyle is best known for being the author of the best-selling book American Sniper: The Autobiography of the Most Lethal Sniper in U.S. Military History. The book recounted Kyle's military career detailing his 150-plus kills of insurgents from 1999 to 2009.

According to the Associated Press, the 38 year-old Kyle and a second man, 35 year-old Chad Littlefield of Midlothian were found dead at the Rough Creek Lodge's shooting range west of Glen Rose.  Glen Rose is located about 50 miles southwest of Fort Worth.

Witnesses told Erath County Sheriff's investigators that a gunman opened fire on the men around 3:30 p.m. Saturday, then fled in a pickup truck belonging to one of the victims, according to the Fort Worth Star-Telegram. WFAA reports the suspect arrested is 25 year-old Eddie Routh. He was taken into custody in Lancaster, southeast of Dallas, and that charges were expected to be filed.