Suspected Taliban fighters attacked southern Afghanistan police posts, triggering clashes and NATO air strikes that left 25 civilians and 20 insurgent fighters dead, a senior police officer said Friday. The insurgents attacked police and used civilian houses for cover in Helmand province's Gereshk district late Thursday, said provincial Police Chief Mohammad Hussein Andiwal. NATO responded by calling in air strikes that killed 20 suspected insurgent fighters -- but also 25 civilians, including nine women and three babies, Andiwal said. NATO said the aircraft struck after insurgents attacked troops from its International Security Assistance Force 14 kilometers (9 miles) northeast of Gereshk town. "A compound was assessed to have been occupied by up to 30 insurgent fighters, most of whom were killed in the engagement," a NATO statement said. "We are concerned about reports that some civilians may have lost their lives during this attack," said an ISAF spokesman, Lt. Col. Mike Smith. Taliban used at least two civilian compounds for cover during the clashes, which lasted into early Friday, Andiwal said.