
The explosion occurred on a road island in front of a petrol station in Moo 7 of Krong Pinang subdistrict's Tambon Krong Pinang at 8.25am.
Police said four soldiers on two motorcycles were riding past the spot when insurgents detonated the bomb to ambush them.
Sergeant Anuchit Thansopha suffered a broken right arm, while Private Sarawut Kaewket was hit by shrapnel in his torso and legs. The two were rushed to Yala Hospital.
Police took five young men in for questioning after detecting traces of gunpowder on them.