A United Nations report on Friday blamed rebel forces for most of the atrocities during an attack on Sierra Leone's capital Freetown last month, but also accused the Nigerian-led intervention force of carrying out executions.

A spokesman for Ecomog, Lieutenant Chris Olukolade, is reported as saying he was not aware of any such killings.

He said Ecomog had no mandate to execute anyone, and its soldiers had always exercised restraint.

The UN document said that there had been reports that the West African peacekeeping force Ecomog had been "summarily executing detainees who were allegedly either rebels or rebel sympathisers".

Casualty figure not known

Jon Leyne reports: Much of the killing was entirely arbitrary

The report also said that the actual number of civilian casualties suffered during last month's attack on Freetown would never be known, although one mortuary worker said on 25 January that over 2,000 bodies of men, women and children had already been disposed of.

A large number of bodies were believed to have been left in ruined buildings or to have been hastily buried on waste ground.

Since rebel forces had renewed their offensive against Sierra Leone's democratically elected government in December, conservative estimates put the total casualty figure at between 3,000 and 5,000, said the UN report.

Many rebel soldiers were children, the report said

It says the rape of women and girls appears to have been standard practice for the rebels.

Many of the soldiers on the rebel side were children, with some as young as eight.