Policeman Hatim Abid, who was at the scene, said four police were among the dead, and the rest were civilians. Police Major Fawzi Hamad said the wounded included three children and two women.
The blast set half a dozen cars ablaze in Ramadi, 100 kilometers (60 miles) west of Baghdad, capital of the vast desert region that was once the heartland of Iraq's Sunni Arab insurgency.
Police checkpoints have been a favorite target of insurgents seeking to show that Iraqi security forces are still unable to keep Iraqis safe as US troops gradually withdraw.
Western Anbar province, controlled by al Qaeda in the years following the US-led ouster of Saddam Hussein in 2003, has been relatively quiet since influential tribal sheikhs joined forces with US troops to drive out the Sunni militants in 2006. But sporadic attacks continue. US forces are due to halt combat operations entirely next summer and withdraw all forces by the end of 2011.