Thailand's southern region has experienced its deadliest attack in years.
Suspected separatist insurgents stormed a checkpoint in its Muslim-majority south, killing at least 15 people - including village defense volunteers and a police officer.
The late-night shooting also saw attackers in Yala province use explosives, and scattered nails on roads to delay pursuers late Tuesday night.
There was no immediate claim of responsibility, as is common with such attacks.
A decade-old separatist insurgency in overwhelmingly Buddhist Thailand's largely ethnic Malay-Muslim provinces of Yala, Pattani, and, Narathiwat has killed nearly 7,000 people since 2004 - according to a group that monitors the violence.
Authorities arrested several suspects from the region in August, over a series of small bombs detonated in Bangkok, though no insurgent group has been blamed directly.
The main group, the Barisan Revolusi Nasional, denied responsibility for the those attacks - which wounded four people.
Again in August, the group told Reuters it had held a secret preliminary meeting with the government.
But any moves toward peaceful resolutions appeared to wither, after the deputy prime minister rejected a key demand for the release of prisoners.