BBC News with Iain Purdon

As thousands of refugees continue to pour across the Libyan border into Tunisia to escape the turmoil now engulfing the administration of Colonel Muammar Gaddafi, aid officials are warning of a growing humanitarian emergency. A UN refugee official, Liz Eyster, said that 50,000 had crossed from Libya, nearly half of them Egyptians, and the immediate aim was to find adequate food and shelter for them.