The attack occurred on the Manangkuapoh-Tanyongmus Road in Tohphoka village in Tambon Tanyongmus in Rangae district at 3:10 pm.
The two injured defence volunteers were identified as Mahama Paoyijehsoh, 46, and Li Dona, 29. They were severely injured by bomb shrapnel and rushed to the Narathiwat Provincial Hospital.
The two were riding on a motorcycle along with two other volunteers on another motorcycle to provide security for a sport competition when insurgents detonated the bomb used a wired remote.
The insurgents then opened fire at the volunteers and the two sides exchanged gunfire for about five minutes before the insurgents retreated.