Security in the deep South has been further tightened after rocket-like devices were discovered in Pattani's Nong Chik district last week.
Security officers found five metal pipes about 120-centimetres long shaped like rockets on the Hat Yai-Pattani Road on Thursday.
Three of them had already exploded but the rest were still intact.
The explosives had stickers attached reading "Nampra Army".
Pattani forensic officials collected the bombs and other evidence from the scene for further investigation to determine the kind of explosives.
They said this was the first time such weapons were used in the region and that they had been designed for maximum impact.
Judging from the location, officers believe that the insurgents wanted to test the bombs, not to attack anyone.
Patrols and military bases were put on high alert, as they could be the prime targets.
The Nampra Army, a faction of the separatist Patani United Liberation Organisation (Pulo), issued a statement warning Thais living near Thai military camps in Pattani and Narathiwat to move from the areas. It said it would launch missile attacks on the camps this year to mark the 48th anniversary of Pulo, so they would celebrate it by targeting the military camps, which it said are under the control of the Martyr Pak Wei group from the Martyr Muzzafar Wing of the Nampra Army.
"We, the Pulo, are not responsible for any incident that may occur that could result in individuals being wounded or killed."
The faction is under the Sweden-based Kasturi Mahkota.
Kasturi has been involved in regular discreet talks with the Thai government since the Surayud Chulanont administration. His faction is also part of MARA Patani, an umbrella organisation that was launched last August.
The group is made up of six separatist movements, all of which have expressed the desire to engage in a peace dialogue with the Thai government on condition that the Thai state officially recognises them as an official entity with legal and diplomatic immunity.
Bangkok has remained tight-lipped in the face of these demands.
Malaysia has been facilitating this series of discussions between the separatists and the Bangkok government that was launched on February 28, 2013 by the Yingluck Shinawatra administration.