US special forces Afghan helicopter downed 'by Taliban' Published duration 6 August 2011

media caption BBC's Quentin Sommerville in Kabul said the crash was a very significant loss for the international mission in the country

Thirty US troops, said to be mostly special forces, have been killed, reportedly when a Taliban rocket downed their helicopter in east Afghanistan.

Seven Afghan commandos and a civilian interpreter were also on the Chinook, officials say.

US sources say the special forces were from the Navy Seal unit which killed Osama Bin Laden, but are "unlikely" to be the same personnel.

This is the largest single US loss of life in the Afghan conflict.

The numbers of those killed have now been confirmed by the Nato-led mission in Afghanistan.

The Chinook went down in the early hours of Saturdayin Wardak province, said a statement from President Hamid Karzai's office.

It was returning from an operation against the Taliban in which eight insurgents are believed to have been killed.

A senior official of President Barack Obama's administration said the helicopter was apparently shot down, Associated Press news agency reports.

An official with the Nato-led coalition in Afghanistan told the New York Times the helicopter was hit by a rocket-propelled grenade.

The BBC's Quentin Sommerville in Kabul says it is rare for the Taliban to shoot down aircraft.

The Taliban say they have modified their rocket-propelled grenades to improve their accuracy but that may not be true, our correspondent says.

'Enemy activity'

"The president of the Islamic Republic of Afghanistan expresses his sympathy and deep condolences to US President Barack Obama and the family of