There have been reports of at least two new attacks Tuesday against Iraq's police force.
Iraqi police officials in a town south of Baghdad say nine police trainees were killed when gunmen drove up alongside the minibus carrying them to work and opened fire.
Earlier, authorities in northern Iraq say two policemen were killed and two others wounded in a drive-by shooting in the city of Kirkuk. The unidentified gunmen escaped.
Hundreds of policemen and other Iraqis working with the U.S. led coalition have died in attacks by insurgents.
In another development, police clashed with demonstrators in the town of Ramadi during protests against Israel's killing of the leader of the Palestinian militant group, Hamas. Demonstrators burned a police car and threw objects at security forces. Police say at least two people were wounded.
On Monday, two Iraqi civilians were killed and several others wounded when a car bomb exploded outside a U.S. air base north of Baghdad. And two Finnish businessmen were gunned down in the Iraqi capital.
Some information for this report provided by Reuters and AP.