LONDON - The spotlight fell on Britain's secretive special forces on Wednesday, with soldiers more accustomed to operating in the shadows finding their pictures splashed across the newspapers and television.

British officials routinely refuse to comment on the activities of members of the Special Air Service Regiment, but reports from Afghanistan said they and U.S. counterparts had played a key role against Taliban fighters.

SAS soldiers were shown in newspapers and on television with their faces wrapped in chequered scarves, their hands raised to shield their identities from the cameras. Some were shown with their faces blanked out, but others were not.

They carried the U.S. M16 rifles favoured by British special forces and were seen travelling in British Land Rover four-wheel-drive vehicles.

A man who appeared to be a member of a U.S. unit sought unsuccessfully to prevent camera crews from filming.

The identity of special forces members is a sensitive topic for the British Defence Ministry, which is anxious to protect their personal security.

British Defence Secretary Geoff Hoon said on Monday that four SAS men had been flown back to Britain after being wounded in Afghanistan but he refused to go into detail.

"British forces have been active on the ground inside Afghanistan for some time. Working closely with U.S. forces they have been engaged in a range of operation tasks in different parts of Afghanistan," he said.

With the latest pictures, the SAS has not been seen so publicly in action since it stormed the besieged Iranian embassy in London in front of live television cameras 20 years ago.

The regiment won few friends among Irish republicans when it was sent into Northern Ireland to fight the IRA. It has also seen action in the 1982 Falklands War and the 1991 Gulf War.

British newspapers said SAS men had played a key part in a bloody battle to crush an uprising of Taliban prisoners at Qala-i-Jhangi, a fort on the outskirts of the northern town of Mazar-i-Sharif.

The British troops were advising anti-Taliban Northern Alliance commanders while taking part in the fighting themselves.

Taliban prisoners were reported to have seized weapons and turned on their captors, with hundreds said to have been killed in the bloodiest fighting so far in Afghanistan's latest war.

The human rights group Amnesty International called on the Northern Alliance, the United States and Britain to investigate the clashes.

Apart from the SAS men, Britain has a small contingent of commandos at the Bagram airbase near Kabul.

Hundreds of U.S. marines have taken control of a desert airbase near Kandahar, stepping up their pursuit of Osama bin Laden, the Saudi-born extremist Washington holds responsible for the September 11 attacks on the United States.