At least 33 people have been killed in a coordinated suicide car bombing and gun attack on police headquarters in northern Iraq.
A car bomb was set off by a suicide attacker before armed militants stormed and sought to take control of the compound in the city of Kirkuk, police said.
A further 70 people were also injured in the the deadly attacks - shattering a relative calm in recent days in the war-torn country.
The attackers struck during the morning rush hour in the city centre, Brigadier General Natah Mohammed Sabr, head of the city's emergency services department said.
In addition to the casualties, the blast caused extensive damage to nearby buildings.
No group immediately claimed responsibility for Sunday's attack.
Kirkuk, an ethnically mixed city, is at the centre of a dispute over oil and land rights between Baghdad's central government and the autonomous northern Kurdish region.
The unresolved row is persistently cited by diplomats and officials as the biggest threat to Iraq's long-term stability.
Tensions between Shiite, Kurdish and Sunni factions in Iraq's power-sharing government have been on the rise this year.
Militants continue to strike almost daily, and carry out at least one big attack a month.
The latest violence comes amid weeks of protests calling for Prime Minister Nuri al Maliki to resign.