By the BBC's Catherine Davis

The war on terrorism was characterised by President Bush as a confrontation between right and wrong.

But reports are now surfacing which suggest that the distinction between right and wrong has been badly blurred inside the walls of the mud-fort at Mazar-e-Sharif.

On Tuesday, Northern Alliance forces, directed by British and American special forces and assisted by US warplanes, ended a revolt by Taleban prisoners.

Viewed from any perspective, I think you'd have to say it's pretty horrific

Simon Brooks, ICRC

Virtually every single one of the 600 mainly foreign Taleban fighters were killed in the end, although there still appears to be resistance from some prisoners hiding in a basement.

Photographers who went in after the battle said at least 50 Taleban were found with their hands tied, suggesting, among other possibilities, that they may have been killed after they surrendered.

The International Committee of the Red Cross (ICRC) is now overseeing the removal of the dead.

Stretchers are brought to the back of a truck and hauled inside. The corpses are tipped onto a heap of bodies.

With the doors secured, the trucks drive out of the fort along a track littered with debris from three days of heavy fighting.

Disturbing scene

Simon Brooks, head of Red Cross operations in northern Afghanistan, said the priority is to process the dead bodies as quickly as possible.

"Viewed from any perspective, I think you'd have to say it's pretty horrific. I mean you can see the extent of damage which surrounds us here," he said.

General Dostum was not in Mazar when the revolt began

He said the exact death toll is not yet known, but the number is large and the condition of the corpses "disturbing".

Walking further into the fort, the scene quickly becomes a wasteland.

By late afternoon it was missing the scores of bodies that had lain there earlier in the day. The dead horses remained, though.

Around the perimeter of this southern section many buildings have been reduced to rubble.

Bricks are blackened by fire, windows are shattered. In some areas the ground is smouldering.

All around, a carpet of spent shells and mortars and twisted metal.

Tied hands

On three tanks Northern Alliance fighters sat, Kalashnikovs and grenade launchers at the ready.

Others guarded the entrances to a basement, their guns pointed into the gloom below.

I sent to them one of my generals, Mr Syed Karmal, to calm them and assure them that no-one will do any harm to them

General Dostum

General Dostum warned that two Taleban prisoners were still at large, concealed among the corpses.

A few hours later a grenade was thrown into the basement.

As the clearing up process continues, opposition fighters pick through the rubble. Often shoes are taken from the corpses.

Difficult assessment

The International Committee of the Red Cross (ICRC) was already in the fort on Sunday when the revolt broke out.

The Red Cross has been trying to process the dead

"We were here to try and access the detainees before this broke out and we were about to gain access to them," said Mr Brooks.

He said the Red Cross would have monitored the conditions of detention and, if anything needed addressing, could have negotiated directly with the authorities.

But, Mr Brooks said, "to speculate on whether or not this was linked to mistreatment I think is not something that we could do at this point in time."

Many of the bodies have now been removed and a full assessment would be difficult.

General Dostum, meanwhile, has denied that the prisoners were tied up or mistreated.

Alliance account

"I sent to them one of my generals, Mr Syed Karmal, to calm them and assure them that no-one will do any harm to them. That they will be given up to the United Nations and treated fully according to international conventions and humanitarian rights," the General Dostum said.

"But they once more attacked my general. They threw another grenade which injured Mr Syed Karmal and also they attacked some of the soldiers and took their guns."

This was General Dostum's account of how the revolt started.

He was absent at the time, in Kunduz, overseeing negotiations for the city's surrender.

But as he surveyed the damage to the fort, his headquarters, the general acknowledged that some of the Taleban prisoners brought there had not been properly disarmed.

Nonetheless, it is still not entirely clear what sparked the revolt - an uprising which has left hundreds dead and a scene of devastation.