At least 15 more Iraqi police and national guardsmen have been killed, as insurgents press their campaign to disrupt upcoming national elections.

A suicide car-bomb explosion in Baghdad near the headquarters of Prime Minister Iyad Allawi's political party killed two police and a civilian and wounded more than 20 people.

North of the capital, U.S. authorities say a car bombing near a U.S. military base in Balad killed four Iraqi guardsmen and wounded 14.

In Tikrit, six guardsmen were reported killed by roadside bombs, and two more Iraqi officers were killed at a checkpoint in the nearby town of Baiji. Separately, officials say a policeman was killed in Mosul when he tried to move a decapitated body that was rigged with explosives.

Security officials say they expected an increase in insurgent attacks before January 30 elections.

Some information for this report provided by AFP and Reuters.