PM tells Thailand to brace for more bombs

Diplomats said a Foreign Ministry briefing on Thursday had failed to provide much by way of reassurance or answers.

"There was no evidence whatsoever," one diplomat said. "It was not exactly enlightening."

Ministry spokesman Kitti Wasinondh told a news conference that investigators were struggling to find witnesses and that much of their work centered on security footage and forensics. "It might be some time for the results of that to come," he said.

General Saprang Kalayanamitr, the most outspoken member of the Council for National Security (CNS), as the coup leaders now call themselves, said the authorities had video surveillance tapes from two of the bomb sites but no clear suspects.

"The people who did it must have been trained for that, or familiar with it. Gangsters, mafia or well-known people were not able to do it," he told a Bangkok radio station.

Security analysts said it was impossible to rule out completely the groups behind the campaign of violence in the three southernmost provinces, the only Muslim-majority region of overwhelmingly Buddhist Thailand.

Since that campaign began with a raid on an army barracks on January 4, 2004, more than 1,800 people have died in daily shootings and bombings.

But the violence has never moved outside the immediate vicinity of the Malay-speaking provinces of Yala, Narathiwat and Pattani, which Bangkok annexed a century ago.

Although many of the bombs in the far south have used ammonium nitrate fertiliser as explosive -- as did the Bangkok bombs -- analysts said their wide geographical spread across the capital was very different.

"This has to be in some fashion linked to the former regime -- but that's such an enormous pool of people," said security analyst Brian Dougherty of Hill and Associates in Bangkok.

(Additional reporting by Panarat Thepgumpanat)