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.