Kabul, Afghanistan (CNN) The Taliban launched a brazen attack on the strategic Afghan city of Ghazni, south of the capital Kabul, early on Friday, seizing key buildings and trading fire with security forces.

Afghan soldiers fought back as the heavily armed militants converged from four sides of the province. At least 16 people were killed and 40 injured, the majority of them Afghan security forces, Ghazni public health director Zahir Shah Nikmall told CNN.

United States forces responded to the assault with attack helicopters and a drone strike, according to US Forces Afghanistan spokesman Lt. Col. Martin O'Donnell.

Heavy fighting was continuing as of Friday afternoon in the city, where Afghan and NATO forces were engaging fighters "by air and ground," Ghazni government spokesman Mohammad Arif Noori told CNN.

Mohammad Radmanish, spokesman for the Ministry of Defense, said that the Taliban had been pushed back to the outskirts of the city.

Read More