It happened Saturday at a Texas gun range.
The victims are identified as 38-year-old Christopher Kyle, who was reportedly born in Odessa, and 35-year-old Chad Littlefield.
Kyle is known as the deadliest sniper in U.S. history for his accuracy in killing insurgents in Iraq. He served four tours of duty in Iraq and wrote a best-selling book about it.
Erath County Sheriff Tommy Bryant explains what happened.
"Around 3:15, Christopher Kyle, Chad Littlefield, and Eddie Ray Routh, I think, it's R-O-U-T-H, they entered the Rough Creek Lodge and went to the shooting range. Around 5 pm, a hunting guide at Rough Creek Lodge came across the two victims and saw that they looked like they had been shot. They were unconscious, went to the Lodge and called 9-1-1. Deputies responded to the lodge and found the two victims. They did appear to be shot. They were deceased. The suspect, Eddie Ray Routh, I believe it is pronounced, had left in the vehicle that belonged to Mr. Kyle. A description was given over the radio, all-points bulletin was given out, black Ford pick-up, had a lift kit on it, had a sticker of a skull on the back windshield. It's my understanding that the suspect left and drove to Midlothian, where he went to his sister's home and told his sister and his bother-in-law what he had just done, then he left there. They called Lancaster Police Department and they notified us. Around 9 pm they spiked his tires, the vehicle was stopped and he was apprehended without any scuffle or fight."
Routh, a 25-year-old former Marine and expert marksmans, is charged with capital murder and is jailed on a 3-million-dollar bond.
There's no word yet on a motive in the killings but police say he may have been suffering from a mental illness.