The officer said a warplane from the international coalition against IS had destroyed a compound used by the organisation in Danadish village, near the town of Hawijah.
"Nine of them were killed, 11 wounded, five vehicles and 13 cases of ammunition destroyed," he told AFP, speaking on condition of anonymity because he was not authorised to talk to the press.
He said the unit's military leader, whom he named as Abu Abed Ahmed Abdallah al-Dandushi, and 30 other IS fighters had managed to flee after the strike, which was carried out at around 7:00 am (local time).
"The coalition strike was very accurate and destroyed this compound which was being used as a shelter for fighters coming from Raqa (in Syria) before they were dispatched to (the provinces of) Anbar, Salaheddin or Diyala," he said.
It was not immediately clear which air force carried out the strike.