Southern MPs are pressing the government to review the enforcement of two laws, which they say have fostered unrest in the far South.
Eleven MPs led by Alidan Aleehas-ho, a Yala MP of the ruling Palang Pracharath Party, said on Wednesday the group plans to have a private meeting with Prime Minister Prayut Chan-o-cha, who is also defence minister, to raise southern security problems with him.
The MPs believe the enforcement of two laws in the far South -- the royal decree on administrating the emergency situations and the martial law act -- which were supposed to contain the violence, have had the opposite effect.
The MPs, including Soekarno Matha of the opposition Prachachat Party, said enforcement of the laws should be reviewed as it has met fierce resistance from insurgents.
On Tuesday evening, police began a hunt for attackers responsible for a pipe bomb and gun attack on security personnel that killed four of them in tambon Paka Harung, Pattani.
Pol Maj Gen Piyawat Chalermsri, commander of the Pattani provincial police, said investigators believed the attackers were in hiding in the province.
About 10 insurgents are thought to have been involved, according to the Internal Security Operations Command's (Isoc) Region 4 Forward Command.
The police commander said insurgents were demonstrating their capability to engineer attacks on authorities.
According to a police investigation, 11 personnel including military officers and security volunteers were stationed at a 24-hour checkpoint at the time of the attack, which took place about 8.45pm.
Armed insurgents hid in bushes close to the checkpoint, keeping watch on the personnel for some time before they threw two pipe bombs at them from a distance.
The explosions wounded many of the officers. The attackers also fired gunshots at personnel guarding the checkpoint, prompting a return of fire. This led the attackers to retreat and flee.
Four security personnel were killed -- Usman Yasaree, Abdul Fateh Semram, Usman Tasamoh and St Maj Chuthawat Massee. Usman Yasaree and Abdul, both of whom were members of a village protection squad, died at the scene. The other two were pronounced dead later.
Two other protection squad members, identified as Paisal Moosordee and Niamin Machamae, were seriously wounded.
Police collected spent shells from assault rifles as evidence.