Military forces of two Burmese ethnic groups engaged in intense fighting along the border with Thailand earlier this week.
Sources say the fighting broke out Tuesday between forces aligned with the Wa and Shan groups near Thailand's northern Mae Hong Son province. The battle began after talks to resolve several issues broke down, including a dispute over water use.
There is also speculation that illegal drugs also played a part in the fighting.
Thailand has increased security along the Burmese border to keep the violence from spilling over into its territories.
Information for this report is provided by AFP.