The detonations, fortunately, inflicted no casualties but damaged several buildings, including a police station in Satun, Channel 3 broadcaster reported Sunday.
Satun and Phatthalung are situated close to Thailand's southern-most Narathiwat, Yala and Pattani provinces. They border Malaysia and are majority-Malay and predominantly Muslim, whereas the rest of the state is mostly populated by Buddhists.
Violence in the region escalated in 2000, and a state of emergency was declared in 2004. Amid the turmoil, several groups of Muslim militants demanded either autonomy for the region or complete secession from Thailand. About 6,500 people have been killed during the ongoing conflict, with the majority of them being civilians.
Thailand is also expected to hold general elections on March 24 — for the first time since the 2014 military coup.