Another soldier was shot dead in Diyala province, The New York Times reported.
Five U.S. soldiers have been killed this month in Iraq. Two members of the Puerto Rican National Guard died Jan. 5 from a bombing in central Iraq.
The Web site icasualties.org reports that 4,435 members of the U.S. military have died in Iraq since the U.S.-led invasion in March 2003. A total of 3,515 died from enemy action, the Los Angeles Times reported.
U.S. soldiers were training Iraqis in techniques used to search buildings and arrest suspects Saturday at Ghazalani Training Center when one of the Iraqis, who had stolen ammunition for his AK-47, opened fire, the Iraqi officer, who asked to remain anonymous, told The New York Times. He killed two and wounded a third U.S. soldier, who was evacuated to Joint Base Balad.
The Iraqi trainee also was killed.
Another Iraqi officer said six people, four of them members of the Iraqi police, were arrested after a bomb hit Forward Operating Base Warhorse in central Iraq.