The sudden upsurge in violence drew speculation the attacks were retaliation for the security forces’ successful raid on a well-hidden insurgent base used by bomb-makers in Pattani on Wednesday.

In Yala, a soldier was killed and another wounded when a roadside bomb exploded in Krong Pinang district yesterday morning.

The blast occurred around 7am near a fruit plantation in tambon Sa-ae, Pol Lt-Col Jaturong |Dorn-onpao, an investigation officer at Krong Pinang police station, said.

The bomb was detonated as a seven-man patrol providing protection for teachers arrived at the spot. Two soldiers were hit by shrapnel – Pvt Sayompu Kaewklum, 22, and Pvt Prasert Immuang, 22. Pvt Sayompu was later pronounced dead at Krong Pinang hospital.

The explosion left a crater about 1.5 metres deep and one metre wide in the ground. Debris, including batteries, was scattered over the area, while a 100-metre-long electric wire was found in nearby trees.

Police blamed insurgent sympathisers active in the area.

Explosive ordnance disposal officers inspecting the scene said the bomb weighed around 5kg and was detonated by batteries connected to the wire.

Two rangers were also injured when insurgents detonated a home-made bomb to ambush a patrol of rangers in Pattani town on Thursday night. The bomb was hidden in a roadside vending stall on Patani-Narathiwat road.

Insurgents detonated the bomb when a unit of eight rangers walked past on a routine patrol at 9pm, police said.

The two rangers slightly injured by shrapnel were identified as Ekkachai Phekhonnu and Khachornsak Ritdam.

At about 4am yesterday, fire broke out at the Ban Khai School in Pattani’s Nong Chik district. No one was injured in the incident but the blaze caused damage to school buildings, including the library. Security officials suspected that the fire may have been arson.