A U.S. soldier has been sentenced to life in prison with the possibility of parole for his role in the execution-style slayings of four Iraqi prisoners.

A U.S. military jury on Friday convicted 28-year-old Sergeant Michael Leahy of premeditated murder in the 2007 killings in Baghdad.

Authorities say the Iraqi men were handcuffed, blindfolded and shot in the head, even though U.S. officials had ordered them to be released because of a lack of evidence.  After being shot, their bodies were thrown into a Baghdad canal.

During the trial in Germany, the nine-member panel heard a videotape in which Leahy tells military investigators he shot one of the prisoners point-blank in the back of the head.

The defense had argued that Leahy's judgment had been affected by a lack of sleep and combat stress.

Two other U.S. soldiers, Sergeant John Hatley, 41, and Sergeant First Class Joseph Mayo, 27, are also charged in the slaying. All were assigned to the First Battalion, 18th Infantry Regiment.

Four other soldiers from the unit have been charged in the murder conspiracy for allegedly going along with the slayings.