FORT WORTH, Texas – The Iraq War veteran charged with killing a former Navy SEAL sniper and his friend on a Texas shooting range had been taken to a mental hospital twice in the past five months and told authorities he was suffering from post-traumatic stress disorder, police records show.

Eddie Ray Routh, 25, also told his sister and brother-in-law after the shootings that he "traded his soul for a new truck," according to an Erath County arrest warrant affidavit obtained by WFAA-TV. Police said Routh was driving the truck of victim and ex-Navy SEAL Chris Kyle at the time of his arrest.

Routh is charged with one count of capital murder and two counts of murder in the shooting deaths of Kyle, author of the best-selling book "American Sniper," and his friend Chad Littlefield at a shooting range Saturday in Glen Rose. He is on suicide watch in the Erath County Jail, where he's being held on $3 million bail, Sheriff Tommy Bryant said.