BAGHDAD (AP) — Iraqi officials say gunmen have downed a military helicopter north of Baghdad, killing its five-member crew.

Two intelligence officers and a military official say the helicopter was shot down while it was providing aerial support to troops on the ground during a gunbattle today with militants outside the city of Tikrit, 80 miles north of the Iraqi capital.

The officers spoke on condition of anonymity as they were not authorized to talk to media.

The fighting was part of the military's counter-insurgency operation recently launched in Sunni-dominated areas in central and northern Iraq. But the operation, dubbed "Revenge for the Martyrs," has not made significant headway in stopping the violence that has gripped Iraq since April.

More than 5,000 people have been killed since then.