Four more US soldiers were killed in separate attacks in the capital this weekend, including three in a single roadside bombing, the military said Monday, pushing the death toll past 100 in the deadliest month so far this year.

In violence Monday, at least 17 people were killed in attacks across Iraq on Monday as insurgents continued to target civilians and police in the country's chaotic capital.

In Baghdad, a suicide bomber blew up a vehicle outside a police headquarters in a western district, killing five people and wounding 12, a security official said.

The Iraqi police have come under heavy fire in recent months as they have struggled to clamp down on the city's daily mayhem as part of a 10-week-old security plan.

Elsewhere in the capital, a former brigadier general in Saddam Hussein's army was shot dead in the volatile Dura neighborhood, and three civilians were killed in two separate roadside bombings.

Another person was killed and nine wounded when three mortar rounds slammed into the northeastern al-Shaab neighbourhood.

The bodies of another three people killed in a gunfight in the capital were brought to Al-Yarmuk hospital in west Baghdad, the hospital said.