Chris Kyle survived four tours of duty in Iraq, becoming the most effective Navy SEAL sniper in U.S. history, but police say that in the end he was killed by a Marine veteran who he was trying to help. Kyle was said to be acting as a mentor to Eddie Ray Routh before Routh turned a gun on him and killed him. The bodies of Kyle and Chad Littlefield were discovered at Texas’ Rough Creek Lodge Saturday evening. Routh was arrested a short time later.

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Casey Stegall provided the latest details in the investigation into the bizarre and tragic crime. Detectives are said to be working to determine how the three men knew each other and for how long. Apparently, they had all ridden in the same vehicle to the gun range. The motive of the attack is still unclear.

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According to police, Kyle and Littlefield had been dead for several hours before their bodies were discovered.

It’s believed that after Routh allegedly shot the two with a semi-automatic handgun, he hopped into Kyle’s car and fled the scene. He led cops on a small pursuit before he was arrested at his home about 75 miles from the range.

There are reports this morning that Routh is being unruly in jail and apparently had to be tasered after attacking jail staff.