Iraqi airstrikes killed nine suspected Islamic State fighters, including four Lebanese, in retaliation for an IS attack on Iraqi army barracks earlier this month, officials said Sunday.

IS gunmen in Iraq broke into a barracks in the mountainous al-Azim district outside the town of Baqouba on Jan. 21, killed a guard and shot dead 11 soldiers as they slept. It was one of the boldest attacks by the militants in recent weeks and came amid an uptick in violence that stoked fears the group has been re-energized.

Yehia Rasool, the spokesman for Iraq’s commander in chief, said the joint military operations room and the air force identified the cell behind the attack as its members hid in al-Azim, north of Baghdad.

Three airstrikes were launched that killed the nine militants, he said.

A security official told The Associated Press that four among the killed were Lebanese, natives of the northern town of Tripoli. He spoke on condition of anonymity because he was not authorized to speak to reporters.