Defence Minister Prawit Wongsuwon has ordered authorities to ramp up efforts to prevent violence in the wake of multiple bomb attacks in Satun and Phatthalung provinces, which he said were intended to discredit the government.
"The act was likely to be done by those who lost benefits and wanted to shake the confidence in the government," Defence spokesman Khongcheep Tantravanich quoted Gen Prawit as saying.
Lt Gen Khongcheep said Gen Prawit has called for tightened security and urged intelligence officials to put heavy emphasis on coordinated intelligence gathering after the explosions.
In Satun, four bombs went off late on Saturday night and early Sunday, the first two at the provincial police office and the other two in front of a grocery shop in Muang district.
In Phatthalung, it was reported that 10 bombs were found in Phatthalung's Muang and Pak Phayun districts. Some bombs exploded and the others were detonated by bomb specialists.
The explosions in both provinces all took place on Saturday night and Sunday morning but caused no deaths or injuries.
As the cases of violence took place in two provinces, administrative and security officials in the South, including in Songkhla, Trang, Phangnga and Yala, have also beefed up security.
Col Pramote Prom-in, spokesman for the southern region office of the Internal Security Operations Command (Isoc), said investigators did not rule out any possibilities as to who was behind the blasts.
He said the explosions could be related to the insurgency in the deep South, political conflicts, or human and drug traffickers taking revenge after recent crackdowns.
However, he admitted that a motorcycle used to deliver a bomb that exploded in Satun was stolen from Songkhla.
Prime Minister Prayut Chan-o-cha has expressed concerns over public safety and advised members of the public not to panic as the situation remains under control, said deputy government spokesman Werachon Sukondhapatipak.
He said the prime minister has instructed security units to be on alert for possible violence, monitor activities of suspected groups and track down the perpetrators.
According to Lt Gen Werachon, local officials are gathering evidence and trying to establish the motives for the bombings.
"There is a possibility that the attackers wanted to cause unrest before the general election," he said.
National police chief Chakthip Chaijinda has ordered security stepped up particularly at government offices, tourist attractions and business centres in the wake of the attacks.
Army and police officers question a shop operator about the bomb that went off close to her store.
Pol Col Kritsana Pattanacharoen, the Royal Thai Police spokesman, said more security checkpoints and patrols are being deployed as part of tightened security.
In Phatthalung, six explosions were reported in Pak Phayun district and three others in Muang district.
A 10th bomb was found near rail tracks in Muang district and detonated by bomb specialists.
In Satun, one bomb exploded in a garbage bin near a power post in front of the provincial police office on Yatra Sawasdee Road about 10.16pm on Saturday. While explosive ordnance disposal police were examining the spot, another bomb went off at 10.44pm about 20 metres away in an area holding impounded vehicles.
Two other bombs exploded in front of a grocery shop at Moo 6 village in tambon Khlong Khut of Muang district: one at 4.20am and the other at 5.10am Sunday. There were no reports of any casualties.
Kongsakul Chantharat, chief of Satun's Muang district office, said an investigation is under way to establish a motive for the bombings.
The tourism business community on the resort island of Lipe in Satun Sunday ruled out the insurgency as a motive in the wake of four explosions in Muang district, saying the violence is likely to be politically motivated and the impact will be short-lived.
According to tourism operators, Satun has witnessed no insurgency-related violence or experienced any tension for years and the bombings might have been triggered by fierce election competition.
- Earlier development: Motorcycle used in bombing stolen in deep South