Iraqi gunmen opened fire on a coalition military patrol outside of the encircled southern city of Najaf (search), killing one soldier, a top U.S. officer said Saturday.

It was not immediately clear if the casualty was an American.

Two gunmen also were killed in the incident, Brig. Gen. Mark Kimmitt (search) said at a Baghdad briefing.

Some 2,500 U.S. soldiers have encircled Najaf and are demanding that an anti-American militia inside disband and its leader, a radical cleric, surrender to Iraqi authorities.

Spanish and Salvadorian troops also are based in the area.