A suicide truck bomb has killed 25 people and wounded 44 others north of Ramadi, the capital of Anbar province, police have said.
The attack took place near a makeshift football field and market in the Albufarraj area, as a police patrol passed by.
Colonel Tareq al-Dulaimi, the local security chief, said: "There was great damage to buildings at the scene, which is a built-up residential area."
Ramadi, 110km west of Baghdad, is the capital of the volatile Anbar province, a stronghold of Sunni Arabs.
Fighters from al-Qaeda and local Sunni tribes are engaged in a bitter power struggle in the province.
Iraqi police and soldiers are often attacked in the area, accused of being traitors by al-Qaeda and local Sunni fighters for collaborating with the US-led coalition and Iraq's government.
Three suicide car bombers killed 20 people and wounded 35 others in Ramadi on Monday.