The government in Sri Lanka says at least 10,000 civilians in the past four days have escaped the country's war zone where troops are battling Tamil Tiger rebels.
US Secretary of State Hillary Clinton has led calls for a "temporary no-fire period" to allow more civilians to get out of the combat zone.
The Tigers are fighting for survival after being driven back into a small patch of jungle by a military offensive that threatens to end their 30 year armed campaign for an independent ethnic Tamil homeland.
Government reports of the civilians' movement and recent army advances cannot be verified as journalists, aid groups and international observers are not allowed into the conflict zone.
Sri Lanka's President Mahinda Rajapakse has warned the rebels to surrender unconditionally or be killed.