Iraqi officials say a suicide bomber has blown up a car near the homes of two senior Iraqi politicians in Baghdad. The attack killed two security guards and wounded 12 other people.

The blast happened Tuesday morning in western Baghdad, close to the homes of former Iraqi Prime Minister Ayad Allawi, a Shi'ite, and Sunni lawmaker Saleh al-Mutlaq. Officials say the casualties were guards and police at the checkpoint where the car exploded.

In other violence, a bomb hidden in a corpse killed an Iraqi soldier in southern Baghdad as he went to retrieve the body. Seven other people were wounded.

Late Monday, gunmen on motorcycles killed the head of a Baghdad psychiatric hospital as he was on his way home.

Separately, the U.S. military on Tuesday said coalition forces have detained five people suspected of involvement in Sunday's assassination of the police chief of Babil province, Maj. Gen. Qais al-Maamouri.

A roadside bomb struck the police chief's convoy near the provincial capital, Hilla after he left a U.S. military base.

In another development, the U.S. military says coalition troops captured the leader of a criminal group and 10 other suspects in operations early Tuesday around the capital. The leader is believed to have coordinated attacks against coalition soldiers and Iraqis.

Also, the U.S. military says a suicide car bomber killed an American soldier and wounded two others Monday in Salahuddin province, a mostly Sunni area north of Baghdad.