Deputy Prime Minister Chalerm Yubamrung has defended the intelligence agencies against criticism they are inept following their failure to prevent the deadly bombings in Songkhla and Yala on Saturday.

Deputy PM Chalerm: Don't blame the intelligence agencies.

Mr Chalerm said on Monday the intelligence units were not incompetent.

The attackers  planned ahead and it was difficult to prevent them from implmenting their plans. Even so, the intelligence units will be working in a more integrated manner from now on, he said.

Police had the pictures of the attackers from surveillance cameras and warrants for their arrest would be issued soon, he said.

Prime Minister Yingluck Shinawatra had instructed security personnel in the far South to work more cohesively and increase the number of security checkpoints, he said.

The former police captain said he could not tell whether southern unrest will escalate further, to the level of violence during the Thaksin Shinawatra administration.

"There will be no insurgent attacks in Bangkok, and there's nothing to worry about," Mr Chalerm said.