Three Muslims, Thai police says "insurgents", were killed in a gunfight with a group of Thai paramilitaries on Tuesday in Muslim south.
An armed Thai person was also wounded in the gunfight, which lasted 20 minutes and took place in Pattani.
Yala, Narathiwat and Pattani provinces were once an independent Muslim sultanate known as Patani until occupied by predominantly Buddhist Thailand.
Local Muslims oppose emergency rule Thai government extended repeatedly and the presence of thousands of soldiers deployed including Thais armed by the state.
Human rights groups have previously accused Thai authorities of major abuses in the south, including the use of unnecessary force in the 2004 siege of a mosque in which 32 suspected insurgents were killed.