A bomb and rifle attack has killed at least nine police officers in northern Iraq.

Sunday’s incident occurred near the oil-rich city of Kirkuk, around 290 kilometers (180 miles) from the capital Baghdad.

Islamic State has claimed responsibility for the incident.

IS has already claimed responsibility for the Wednesday roadside bombing that killed three Iraqi soldiers near Baghdad.

Sunday’s incident began when a bomb exploded near the village of Chalal al-Matar and targeted a police truck, according to AFP.

The explosion was followed by “a direct assault with handguns.”

“We have killed one attacker and are searching for the others,” the official said, adding that two police officers were also injured in the attack.

A representative of the Interior Ministry in Baghdad confirmed the attack.

IS once ruled about eight million people in a territory spanning from eastern Iraq to western Syria and covering an area of 88,000 square kilometers (34,000 square miles).

In December 2017, however, Iraqi forces declared victory over the Islamist group after driving IS militants from their remaining strongholds in the Syrian border region.

The group lost its final area in 2019, but the United Nations issued a warning in July that it remained a persistent threat.

It is believed to have between 6,000 and 10,000 fighters in Syria and Iraq, most of whom are based in rural regions and continue to conduct hit-and-run operations, ambushes, and roadside bombings.

In its report, the United Nations said that despite “major leadership losses”, the group has been able to “exploit security loopholes and conditions conducive to the spread of terrorism” to “recruit and organize complicated assaults.”