Two Americans believed to be a U.S. colonel and major were shot dead in Afghanistan's Interior Ministry on Saturday, Feb 25, security sources said, while rage gripped the country for a fifth day over the burning of the Muslim holy book at a NATO base, Reuters reported.

A spokeswoman for NATO's International Security Assistance Force (ISAF) confirmed two of their servicemen had been shot dead in central Kabul by an individual who turned his weapon on them. She declined to say if the killer was a member of the Afghan military or police.

Afghanistan's Taliban movement claimed responsibility for the shootings, which it said were in retaliation for the desecration of the Korans at Bagram airfield.

Taliban spokesman Zabihullah Mujahid said in an e-mailed statement to the media that four high-ranking Americans had been killed, though the Islamist group often exaggerate and inflate claims of casualties.

The Koran burnings underscored the deep cultural divide that still exists more than 10 years after U.S. troops invaded to oust the Taliban and has deepened public mistrust of Western troops struggling to stabilize the country.

An Afghan security source said the shooting of the two Americans in the Interior Ministry could be connected to the burning of the Korans.