Thousands of refugees fleeing violence in the former Soviet republic of Uzbekistan have been heading for neighbouring Kyrgyzstan.
Border crossings have been closed but hundreds of people are said to have forced their way through.
In a town straddling the frontier, refugees clashed with Uzbek police and government buildings were set alight.
Hundreds of people are thought to have been killed when Uzbek government troops fired on protestors in the eastern city of Andijan on Friday.
The bloodshed began when week-long demonstrations over the trial of 23 local businessmen boiled over.
Prosecutors had accused the men of belonging to an outlawed Islamic group, but their supporters said the charges were fabricated.
After armed supporters of the accused stormed a local prison to free the men - along with some 2,000 other prisoners - the military moved into the city that was then was gripped by mass anti-government protests.
Witnesses accused the soldiers of firing indiscriminately into the crowd.
The country's President, Islam Karimov, has denied that the soldiers were ordered to open fire.
Karimov, a 67-year-old Soviet-era leader who is supported by both Moscow and Washington, has blamed foreign Islamic militants for the violence.
