Afghans protest Koran burning at U.S. base Afghan men shout anti-U.S slogans during a protest outside the U.S. military base in Bagram, no...

Afghans protest Koran burning at U.S. base

Afghan men shout anti-U.S slogans during a protest outside the U.S. military base in Bagram, north of Kabul February 21, 2012.REUTERS

Protesters throw stones toward US soldiers standing at the gate of Bagram airbase. AFP photo

Protesters hurling petrol bombs and slingshots besieged the largest US-run military base in Afghanistan on Tuesday, furious over reports that NATO troops burned copies of the Koran

Afghan throw stone towards the US soldiers in front of the US base of Bagram during an anti US demonstration in Bagram north of Kabul, Afghanistan, Tuesday, Feb. 21, 2012.AFP

Afghan protestors are seen in front of the US base of Bagram during an anti US demonstration in Bagram north of Kabul, Afghanistan, Tuesday, Feb. 21, 2012. More than 2,000 angry Afghans, some firing guns in the air, protested on Tuesday against the improper disposal and burning of Qurans and other Islamic religious materials at an American air base in Bagram north of Kabul. (AP Photo/Musadeq Sadeq)

Protesters firing petrol bombs and slingshots besieged the largest US-run military base in Afghanistan on Tuesday, furious over reports that NATO troops had set fire to copies of the Koran. AFP

An Afghan man shouts anti-U.S slogans near a pile of wood and tyres, set on fire by the protesters, during a protest outside the U.S. military base in Bagram, north of Kabul February 21, 2012. Reuters

More than 2,000 angry Afghans protested outside an American air base on Feb. 21 after they learned that copies of the Koran were burned in a pile of garbage at a sprawling U.S. military base north of Kabul.

Afghan officials said. U.S. helicopters fired flares to try to break up the demonstrators.

The US commander in Afghanistan, General John Allen, apologised and ordered an investigation into a report that troops "improperly disposed of a large number of Islamic religious materials which included Korans"