Al-Qaida ally Abu Musab al-Zarqawi's group claimed responsibility Wednesday for a suicide car bombing that killed at least six people outside an army base in western Baghdad, an Internet statement said.

"A lion from the martyrdom-seeking brigade of the Organization of Al-Qaeda of Jihad in the Land of Two Rivers carried out a heroic operation today against a base of the (national) guard in Al-Muthanna airport, killing tens of them," said the statement, whose authenticity has not been verified.

At least seven people were killed and over 20 others wounded when a car blew up Wednesday outside an army base in the western part of the Iraqi capital. The blast targeted people who were lining up for army recruits, witnesses said.

The same base, which was a disused airport, was hit a few hours later in a mortar attack that killed one soldier and wounded nine others.

The Jordanian militant Zarqawi has operated scores of deadly attacks in Iraq, including a powerful car bombing Monday that killed 118 people and wounded more than 200 others in the town of Hilla, south of Baghdad.