Up to 30,000 people have fled fighting in eastern Myanmar's Shan state to seek refuge in the Chinese border town of Nansan, the UN Refugee Agency said on Friday.
"Our information is that as many as 30,000 people may have taken shelter in Nansan county since 8 August, saying they were fleeing fighting between Myanmar government troops and ethnic minority groups," UNHCR spokesman Andrej Mahecic said.
"We have been informed that local authorities in Yunnan Province have already provided emergency shelter, food and medical care to the refugees," he added.
The UNHCR is also liaising with local authorities from southwestern China's Yunnan province on meeting the refugees' needs, said Mahecic.
A battle in Myanmar's remote Shan state between the Kokang rebel group and government troops began on Thursday, breaking a 20-year ceasefire, according to the US Campaign for Burma, which uses Myanmar's former name.
The exodus of civilians began when Myanmar's junta deployed troops in the mainly ethnic Chinese region on August 8.