The explosion in front of a convenience store in Muang district at around 9pm on Friday left a 59-year-old man, identified as Manoon Unok, with injuries to his left arm and right leg.
At around the same time, police also found another suspicious-looking box on Siroros Road. The box, containing gunpowder and an integrated circuit attached to a clock, was defused by the bomb disposal team.
Provincial police chief Pol Maj-General Tinnakorn Rangmart instructed investigators to study all security camera footage from areas around these locations to try and identify suspects. Some of the suspected perpetrators were spotted on the CCTV footage.
Meanwhile, of the 11 suspected explosive devices found, bomb disposal experts managed to defuse three. There were no reports of property damage.
Police believe the perpetrators simply wanted to cause disturbance in the insurgency-hit region.