Representatives of Burma's ethnic Karen refugees say Thailand has turned back more than 200 Karen fleeing a Burmese military offensive.
Karen leaders say Thai border officials on Wednesday stopped the refugees as they arrived in two boats on the Salween River, which separates Burma and Thailand.
Karen sources say the refugees included women and children, many of whom were sick.
Burma's military government intensified its offensive against Karen rebels last year. Rights groups say more than a million people in Burma have been displaced since 1996 due to the violence.
According to the United Nations, about 140,000 Burmese refugees, most of them Karen, live in Thai government-run camps along the border with Burma.
Information for this report is provided by Reuters.