A U.S. Army sniper convicted of killing an unarmed Iraqi civilian and planting evidence on his body was sentenced Sunday to 10 years in prison.

Sgt. Evan Vela faced a possible life sentence. Earlier Sunday, jurors found him guilty of murder without premeditation in the May 11 killing of an Iraqi man south of Baghdad.

Vela was also sentenced to forfeiture of all pay and allowances, and will receive a dishonorable discharge. His case is automatically referred to a military appeals court.

He will be transferred to a U.S. military base in Kuwait, where he will remain until the military decides on a permanent incarceration site in the United States.

Vela had previously been charged with premeditated murder, but that charge was changed during his court-martial in Baghdad. He was also found guilty of making a false official statement and of conduct prejudicial to good order and discipline.

The defendant showed no emotion as the verdict was read. Two of his lawyers leaned over and gave him a light hug over the shoulders before leading him out of the courtroom on a U.S. military base in Baghdad.

Defense lawyers had claimed the killing of Genei Nasir al-Janabi was an accident, brought on by extreme exhaustion and sleep deprivation. But military prosecutors called it a simple case of murder.

"It's a simple case," said Capt. Jason Nef, one of two military prosecutors. "The reason is because Vela confessed on the stand that he lied. He confessed he killed an unarmed Iraqi."

Vela, who is from St. Anthony, Idaho, wept on the witness stand Saturday as he described shooting al-Janabi after he stumbled upon the snipers' hiding place near Iskandariyah, 50 kilometers (30 miles) south of Baghdad.

"I don't remember pulling the trigger. I don't remember the sound of the shot," Vela said in a near whisper, thumbing the hem of his camouflage jacket and looking straight ahead. "It took me a few seconds to realize that the shot came from my pistol."

He testified that after he shot al-Janabi, he tried to shoot him again because "he was convulsing on the ground and I thought he might be suffering."

"I just didn't want him to suffer. It was something I've never seen and I got a bit scared," Vela said. The second shot missed the man.

James Culp, Vela's attorney, had unsuccessfully argued that Vela was too sleep deprived to know what he was doing.

"This was an accident waiting to happen," Culp told the jury of seven men and one woman in his closing argument Sunday. "What happened on May 11 is clear: These men were extremely, extremely sleep deprived and nobody was thinking clearly."

Vela and his sniper team had hiked through rough terrain and slept less than five hours in the 72-hours leading up to the killing, the defense said.

Culp also called two medical experts who testified that Vela was suffering from acute sleep deprivation and exhaustion. They said he later lied about the events in part because he suffers from post traumatic stress syndrome.

On Friday, Vela's commanding officer testified that he ordered Vela to kill al-Janabi, saying that was the only way to ensure the safety of his men in hostile territory.

Sgt. Michael A. Hensley, who was a staff sergeant at the time of the killing but was later demoted, testified that he and the other members of the sniper team had all fallen asleep, then awoke to find al-Janabi squatting about three feet from them.

Hensley said he ordered the man to lie on the ground and was searching him when he saw "military-aged men" who he thought were carrying weapons about 100 yards away.

He said al-Janabi began yelling, and he decided that killing the man was the only way to keep the sniper hide-out from being discovered by what he believed was a group of approaching insurgents.

Hensley, of Candler, N.C., and Spc. Jorge G. Sandoval Jr., of Laredo, Texas have faced similar charges in al-Janabi's killing as well as two other slayings. They were acquitted of murder but convicted of planting evidence on the dead Iraqis.

Sandoval was sentenced to five months in prison, his rank was reduced to private and his pay was withheld. Hensley was sentenced to 135 days confinement, reduced in rank to sergeant and received a letter of reprimand.

The soldiers were assigned to the 1st Battalion, 501st Infantry Regiment, 4th Brigade (Airborne), 25th Infantry Division, based at Fort Richardson, Alaska.

Vela testified at Hensley's court-martial in late September, under a deal that bars his account of events from being used against him at his own court-martial.