A gunman in Afghanistan has killed two American members of NATO's International Security Assistance Force.

NATO said in a statement Saturday that an individual “turned his weapon against” the service members, but did not provide details on who the shooter or the victims were.

Sources are telling reporters that the two victims are Americans.

Afghan officials say the shooting took place inside the Interior Ministry building in Kabul.

Violence erupted across Afghanistan Saturday, the fifth straight day of protests over the burning of Qurans.

Hundreds of rock-throwing protesters attacked a United Nations compound in northern Afghanistan. Officials say at least three people died and 47 were injured in the melee in Kunduz.

Authorities say at least 27 people have died since Tuesday after reports surfaced that NATO troops had burned copies of the Quran at Bagram Air Base near Kabul.

U.S. President Barack Obama and other U.S. officials have apologized for the desecration of the Muslim holy book, but the apologies have done little to quash the outrage in Afghanistan and neighboring Pakistan.

Meanwhile, Afghanistan's defense ministry says six Afghan soldiers were killed and 16 were wounded Saturday while trying to defuse a roadside bomb.

The ministry says the incident happened in the Muqur district of western Badghis province.