KABUL, May 11: An Afghan soldier opened fire on Nato troops in eastern Afghanistan on Friday, killing an American and leaving two others wounded, officials said.

The death brings to 20 the number of Nato soldiers killed by Afghan colleagues in at least 15 separate attacks so far this year.

The shootings have forced US-led troops to step up security and fanned tensions between western soldiers and the Afghan security forces they are supposed to be training to take responsibility for the country by 2014.

“An Afghan army soldier turned his weapon against US soldiers inside an Afghan-US military base in Kunar province, killing one US soldier and injuring two others,” said provincial police chief Ewaz Mohammad Naziri.

The attack took place early Friday and the gunman managed to flee the scene, Naziri said.

The Taliban, which is leading an 11-year insurgency against Nato troops and the Kabul government, claimed responsibility.

Taliban spokesman, Zabihullah Mujahid, claimed in a text message that 12 American soldiers were killed.

The militia frequently exaggerates casualty figures.

Nato ‘s mission in Afghanistan confirmed that a man dressed in local army uniform “turned his weapon against coalition service members” and killed one soldier.

But the International Security Assistance Force gave no further details and said the nationality of the dead soldier would be announced by his home country. It does not list details of the wounded in any attack.

The incident was under investigation, it said.

An increasing number of Afghan soldiers have turned their weapons against Nato troops who are helping Kabul fight a decade-long insurgency by hardline Taliban Islamists.—AFP