Foreign Minister Surakiart Sathirathai said no evidence supported the theory that culprits behind this week's deadly attacks were linked to regional terror group Jemaah Islamiyah (JI), as claimed by a top security official.

"I have not received any hint that they have links with each other. To my understanding this might be personal speculation. We are still in the process of pursuit, making arrests and interrogating," Surakiart told reporters.

"There has been no information to prove such a link."

A report citing Thailand's new security advisor Kitti Rattanachaya Thursday said the assailants were members of a "well-established organisation" fighting to establish an Islamic state in the south.

He said separatists could be getting support from a Malaysian militant group tied to the Indonesia-based JI, which is blamed for several deadly attacks around the region including the Bali bombings which killed 202 people in 2002.

Lieutenant General Jumpon Munmai, chief of the National Intelligence Agency, also dismissed the comments.

"This movement (of attackers) is not related to JI at all," he said.

An editorial in the Bangkok Post Friday said the government was intent on making people believe that no problems were affecting the south at all.

"Denying that a more serious problem exists appears to be a deliberate strategy of this image-focussed administration. This is folly of the most perilous sort," it said.

The government has put forward widely conflicting statements on who it believes may be responsible for the attacks, ranging from local trouble-makers to bandits linked to "mujahedin".

Defence Minister Thammarak Issarangkun Na Ayutthaya backtracked on earlier comments that the arrests of two men allegedly belonging to a local separatist group named Bersatu had taken place.

"They have merely been detained for interrogations while others have been asked in for questioning. If anyone is to be prosecuted I will let you know," he told reporters.

His latest comments also contradicted Prime Minister Thaksin Shinawatra, who earlier said formal charges had been laid against "some" arrested suspects.

Under martial law, clamped down in some districts in the three provinces rocked by the unrest, the military is authorised to detain suspects indefinitely without laying charges.

Thammarak also said authorities had received tip-offs from locals that would lead to more than 100 people being questioned over the violence which included an attack on a military base, the torching of 18 schools and planting of bombs.

A low-level Muslim separatist insurgency has simmered for decades in Thailand's south but it mostly disbanded by the 1990s. It is now dismissed as highly fractured, but organised crime gangs together with Islamic militants are likely to have since linked up in the area, analysts say.

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