Bomb experts successfully defused an explosive device found in a parked pickup truck in Waeng district, Narathiwat province, on Friday.
The school-milk truck was hijacked in nearby Pattani province on Tuesday.
The pickup truck was found next to the Waeng police station at about 11.20am. Security authorities confirmed it was the milk pickup truck hijacked in Sai Buri district of Pattani on Tuesday.
There was a cooking gas cylinder stuffed with 80-100kg of explosives inside the truck. There were also petrol-filled containers inside the vehicle. It was parked near the residence of the chief of the police station.
Witnesses said a man, accompanied by three others on two motorcycles, had parked the truck there. The driver then left with one of the motorcycles.
The discovery of the truck bomb followed an explosion at a plant pot in front of an abandoned food stall opposite the police station at about 6.30am. No casualties were reported.
The incident occurred as Thai security authorities had peace talks with southern insurgents in Kuala Lumpur.
Photos show the hijacked milk truck before and after bombing modifications. (Security officials' photo)
The bombing scene opposite the Waeng police station. (security officials' photo)
A bomb squad is defusing the bomb. (Security officials' photo)