More than 200 bodies have been found abandoned at a hospital in the Libyan capital, Tripoli.
There was no sign on Friday of an end to the war, as intense fighting took place near the international airport in Tripoli, NATO jets bombed Colonel Muammar Gaddafi's bastion in Sirte and rebels prepared for an assault on the town, regarded as his last major stronghold.
Corpses of men, women and children on beds and in the corridors were found in a hospital in Abu Salim, one of the districts worst hit by intense fighting.
A BBC correspondent said the hospital's staff had run away and many injured people had been left to die of their wounds.
Meanwhile, the African Union has failed to recognise the Transitional National Council as the legitimate government of Libya. South Africa's president, Jacob Zuma, says it will not do so while fighting continues.
The UN has already agreed to release $US1.5bn in funds, which had been frozen under Security Council sanctions at the beginning of the uprising in February, to help with immediate humanitarian needs.
However rebel leaders are have calling on other states to unfreeze Libyan assets.
