Insurgents launched a series of coordinated arson and bomb attacks in the deep South late on Tuesday, mostly targeting banks to damage their automatic teller machines.
In two other attacks, one in Pattani fatally wounded a teacher, and the other in Narathiwat killed two Army paramilitary rangers and wounded five others.
Officials said 34 locations were under attack, damaging or gutting a large number of ATM machines belonging to various private and government banks or those attached to convenience stores.
Deputy Prime Minister Pracha Promnog said the attacks were symbolic and marked the anniversaries of two insurgent groups - Barisan Revolusi Nasional (BRN), which was established on October 10, and Patani United Liberation Organisation (Pulo) on October 11.
Three attacks were conducted in the Yawi-speaking district of Saba Yoi in Songkhla, while the remainder, involving either small-sized incendiary bombs or the torching of car tyres to block roads, took place in Pattani, Yala and Narathiwat, said Colonel Pramote Phrome-in, of the Internal Security Operations Centre's forward base.
The military viewed the attacks as attempts to destabilise the region economically apart from demoralising the local public, said the spokesman. The colonel also called on residents to condemn the attacks.
There were no prior warnings from security agencies about the attacks, which are traditionally given at national level and from local offices in charge of security in the deep South.
The death of Waena Munoh, a teacher at Ban Johkeuyae in the Pattani attack on Tuesday night, brought the death toll of teachers to 165.