Security has been beefed up in the restive deep South ahead of the long Songkran holiday next week, following destructive bombing attacks in Yala over the past two days.
Yesterday's bomb explosion at a goods warehouse in Yala municipality led to a blaze that caused at least Bt300 million (S$11.65 million) in damage.
The Sri Samai warehouse is the largest for consumer products in the region and distributes goods to the three southern border provinces of Yala, Narathiwat and Pattani.
A convenience store located next to the warehouse was among four targets attacked yesterday morning.
Authorities in the southern border provinces yesterday began increasing security measures in risky areas.
Yala Governor Dejrat Simsiri said the bombings in the province yesterday and on Sunday were certainly carried out by the same group of people judging from evidence found by investigators.
He said the attacks involved car and motorcycle bombs and were obviously well planned and aimed at undermining the local economy ahead of Songkran.
The governor said the authorities were convinced that yesterday's explosions were caused by time bombs planted around the same time as those that exploded on Sunday.
"The perpetrators timed the bombs to explode at different times in order to make the attacks look worse," he said.
Local authorities have boosted security to the top level and thoroughly scrutinised possible target areas, according to the governor.
He added that security had been provided to individuals who could be targeted by insurgents.
Noppong Thiraworn, head of the Yala Chamber of Commerce, put the warehouse damage bill at an estimated Bt300 million.
The warehouse mainly stored consumer products, electrical appliances and furniture.
Noppong said the economic impact of the attacks was incalculable, with the latest attacks the severest in 10 years.
"The perpetrators certainly wanted to scare away tourists when we expect Songkran to help stimulate the local economy," he said.
On Sunday evening, four almost simultaneous explosions rocked Yala, killing one person and injuring 28 others in the heart of the town.
Yala is one of several hot spots in the predominantly Muslim deep South. Violence flared in the region in January 2004 and since claimed more than 5,000 lives. The authorities believe separatist insurgents are behind most of the violence.
In the neighbouring province of Narathiwat, security has been heightened, particularly in the downtown and business centre, following the attacks in Yala, Narathiwat Governor Nattapong Sirichana said yesterday.
More checkpoints have been set up to screen suspected vehicles entering those areas.
Nattapong said insurgents might attempt to carry out attacks in Muang and Sungai Kolok districts ahead of Songkran, in a bid to scare away tourists.
Security sources said yesterday that the latest attacks could be aimed at challenging the new commander of the Fourth Army Region, Lt-General Walit Rojanapakdee.
The sources said that the bombings had had a severe psychological impact on locals, while the intended message from insurgents could be that they were capable of such attacks at anytime and anywhere.