At least 20 people were killed Wednesday when a car bomb detonated outside a police academy south of Baghdad during a graduation ceremony, police sources said.

The blast took place at the main gate of the academy in Hilla city, some 100 km south of Baghdad, the sources said.

To unseat the Jan. 30 parliamentary elections, insurgents have escalated their attacks against Iraqi officials, US troops and Iraqi security guards to destabilize the situation in the war-ravaged country.

On Tuesday, a suicide tanker bomb exploded near an Iraqi special police base in western Baghdad, killing eight commandos and two civilians, and wounding some 60 others, according to the Iraqi Interior Ministry.