Three Islamic State suicide bombers targeted a police base in Iraq's western Anbar province with explosives-laden trucks, killing at least 35 police and Shiite militiamen.
The attack on a police station in the Tharthar area north of the IS-held provincial capital, Ramadi, caused a large secondary explosion in an ammunition depot, officials said. Another 40 security forces were wounded in the attack.
The attack resembled a massive, coordinated assault launched on Ramadi last month that allowed IS militants to capture the city, marking their biggest gain since a US-led coalition began launching airstrikes against the extremist group last August. In that assault, the IS group also used Humvees looted from Iraqi security forces.
The loss of Ramadi prompted Iraqi Prime Minister Haider al-Abadi to order Shiite militiamen into the vast Sunni province, which was an insurgent hotbed during the eight-year US intervention.
The Shiite militiamen have played a key role in pushing the Sunni IS group back elsewhere in Iraq, but have also been accused by rights groups of carrying out revenge attacks against Sunnis, charges denied by militia commanders.
The IS group and other Sunni extremists view Shiites as apostates deserving of death.