Two Pennsylvania National Guardsmen are being investigated in connection with the shooting death of an Iraqi civilian earlier this year and have not returned to the United States with the rest of their unit, a Guard spokesman said Friday.

The two soldiers, Spc. Nathan B. Lynn, 21, of South Williamsport, and Sgt. Milton Ortiz Jr., 36, of Islip, N.Y., were both members of a combat team whose members began returning home earlier this month after a yearlong deployment.

Lt. Col. Chris Cleaver, spokesman for the Pennsylvania National Guard, said the Army is handling the investigation. He said he could not release other details.

Army Sgt. Doug Anderson, a military spokesman in Baghdad, had no immediate comment.

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The Patriot-News of Harrisburg, which reported on the investigation in Friday's editions, quoted an unidentified member of Lynn's unit as saying that the civilian was shot during a February search of a home in Jazeera, near Ramadi.

Lynn's father, Williamsport police Capt. William Lynn, told the newspaper that his son maintains his innocence. William Lynn did not immediately return a phone message left at his office by The Associated Press on Friday.

Lynn joined the Guard in 2002, Ortiz in 1991; both are with a unit a based in Williamsport.

The allegations surfaced as seven Marines and a Navy medic are facing charges they killed an Iraqi civilian and covered up the crime in April, and four Army soldiers are facing murder charges in the shooting deaths of three Iraq civilians in May. Click here to read the latest on that story.

A group of Marines is also under investigation in the deaths of 24 Iraqi civilians in Haditha last year. Click here to read the latest on the Haditha story.