Up to seven people were killed and some 24 wounded Monday in a suicide car bomb attack near an entrance of Baghdad Green Zone in Iraq, an Interior Ministry source told Xinhua.

"Our latest report said that seven people were killed and 24 wounded by the suicide car bomb explosion at the Green Zone," the source said on condition of anonymity.

The attack took place Monday morning when a suicide bomber drove his explosive-laden car into the checkpoint at one of the entrances of the heavily fortified Green Zone in central Baghdad, the source said.

The blast caused a plume of grey smoke to rise above the scene.

Iraqi security forces sealed off the scene as ambulances and civilian cars evacuated the victims to several Baghdad hospitals and medical centers, the source added.

The Green Zone has been frequently targeted by insurgents' mortar and rocket attacks. The roughly 10 square km zone is located on the west bank of the Tigris River which bisects the Iraqi capital.

Violence and sporadic high-profile bomb attacks are still common in the Iraqi cities despite the dramatic decrease in violence since its peak in 2006 and 2007, when the country was engulfed in sectarian killings.