Baghdad ? A military jury on Sunday convicted an Army sniper of murder and sentenced him to 10 years in prison for killing an Iraqi civilian who wandered into the hiding place where six soldiers were sleeping.

Sgt. Evan Vela, 24, was found guilty of murder without premeditation, of aiding and abetting in planting an AK-47 on the dead man’s body and of lying to military investigators about the shooting. He had faced a possible life sentence.

Vela showed no emotion when the verdict was read, but he asked the jury for mercy before it broke to decide his sentence. He apologized to the court, the Army and one of the sons of Genei Nasir al-Janabi, the man he shot with a pistol in May.

“When I came to Iraq, I didn’t come to do anything wrong,” Vela said, reading from a handwritten statement. “I failed my standards, your standards and the standards of the Army. All I can say is I’m sorry and ask for mercy.”

Vela has been in confinement in Kuwait since July 1. That time will be credited to his sentence, the judge said. He also was sentenced to forfeit all pay and allowances and will receive a dishonorable discharge. The case was automatically referred to a military appeals court.

Vela’s trial was the last of three snipers in the unit accused in a series of shooting deaths south of Baghdad that defense lawyers said happened under command pressure to increase kill counts and, perhaps, employ questionable tactics in doing so.

In September, Gary Myers, then an attorney for Vela, claimed that Army snipers in Iraq were under orders to “bait” their targets with suspicious materials, such as detonation cords, and then kill whoever picked up the items.

The Army has declined to confirm that any such program existed, saying it does not discuss tactics used in the field.

While it does not appear the alleged baiting played in this case, James Culp, Vela’s attorney, and others have argued the program may have encouraged the soldiers by blurring the legal lines in a complex war zone.

Vela and several of his fellow Army snipers testified that they were confused and exhausted after more than two days of trekking in high temperatures through the rough terrain near Iskandariyah, a mostly Sunni Arab city 30 miles south of Baghdad.