Tamil civilians wade across lagoon to escape

Thousands of civilians under rebel fire waded across a lagoon to escape Sri Lanka's war zone, where government forces have surrounded Tamil Tiger separatists for the final battle of a 25-year conflict, the military and a UN official said.

The military said aerial surveillance footage confirmed an exodus of about 5,000 people from a tiny, sandy coastal strip, where the US and others say the Liberation Tigers of Tamil Eelam (LTTE) are holding thousands by force.

Sri Lanka and the LTTE on Thursday brushed off demands from the UN Security Council and US President Barack Obama to take steps to protect the civilians at grave risk who are stuck between two foes determined to fight to the end.

Government doctors whose personal security is at the whim of the Tigers said constant shelling had prompted them to give up work at the only clinic left in the war zone, where 2,000 patients needed treatment.