At least 56 people have been killed and hundreds of homes torched since Sunday, as clashes spread in Myanmar's Rakhine state, officials say.
Several people were killed overnight as violence erupted despite a night-time curfew in at least two towns.
The latest clashes are the first serious outburst of violence since June when a state of emergency was declared in the western state after 90 people were killed.
That outburst was triggered by the rape and murder of a young Buddhist woman by three Muslims, and tensions have remained high between ethnic Rakhine Buddhists and Muslims, the BBC reports.
There is long-standing tension between the Rakhine , who make up the majority of the state's population, and Muslims, many of whom are Rohingya. The Myanmar authorities regard the Rohingya as illegal immigrants and correspondents say there is widepsread public hostility to them.
The United Nations describes Rohingya as a persecuted religious and linguistic minority from western Myanmar. The Myanmar government, on the other hand, says they are relatively recent migrants from the Indian subcontinent.