A 21-year-old Portsmouth, Va., native was killed by a sniper while on guard duty in Mosul, Iraq, the Defense Department said yesterday.

Pfc. Andrew L. Tuazon, who was most recently living in Chesapeake, Va., was a military policeman assigned to the 293rd Company, 3rd Battalion, 3rd Infantry Division at Fort Stewart, Ga., officials said.

A news release from the Defense Department said that he was killed Monday "from hostile fire" and that the incident was under investigation.

Lt. Col. Diane Battaglia, a U.S. Army spokeswoman, said Tuazon was shot by a sniper, not in "an exchange of gunfire."

Dov Schwartz, another Army spokesman, said Tuazon apparently was alone when he was shot.

A spokeswoman at Fort Eustis in Newport News, Va., said Tuazon's mother and stepfather were too upset to speak publicly about his death. Fort Eustis helps military families in the region when someone is hurt or dies.

No local service was immediately scheduled, but a memorial ceremony was planned Tuesday morning at Fort Stewart.

Tuazon, who joined the Army in November 2002 and had served in Afghanistan, spoke to a Fort Stewart Army newspaper when his unit left for Iraq in March. With relatives and friends waving goodbye to the soldiers, Tuazon told the Frontline newspaper that he was anxious to leave.

"A year is a long time," he said, "but I can't wait to leave so I can hurry up and get back."

Pfc. Andrew Lee Tuazon, before taking off for Iraq from Fort Stewart.