Baghdad, Iraq ? A U.S. military judge convicted an Army sergeant of murder Friday for the alleged mercy-killing of a severely injured Iraqi teenager, and sentenced him to a year’s imprisonment.

Staff Sgt. Jonathan J. Alban-Cardenas of Inglewood, Calif., is the second soldier convicted of shooting the wounded 16-year-old as U.S. forces battled an uprising in Baghdad’s Shiite Muslim stronghold of Sadr City in August.

Alban-Cardenas is a member of the Fort Riley, Kan.-based 41st Infantry regiment. In past news releases, Fort Riley has identified him as Staff Sgt. Cardenas J. Alban, and Army officials in Baghdad and Fort Riley could not clarify the discrepancy.

Witnesses say U.S. soldiers found the teenager in a burning truck apparently set alight by the fighting.

The Americans decided severe burns and abdominal wounds put the teenager beyond help and that “the best course of action was to put (the victim) out of his misery,” a criminal investigator has said.

Staff Sgt. Johnny M. Horne Jr. was sentenced in December to three years in prison for the same killing.