Until recently Thailand has denied that Al Qaeda or the closely- affiliated Jemaah Islamiyah (JI) are active inside the country. Prime Minister Thaksin Shinawatra dismissed reports late last year that JI leaders held meetings in Thailand as "fabrications" invented by "crazy people."
But now his country is moving against a hitherto little-known cell in its southernmost provinces, home of a tiny Muslim minority. This week the government foiled attacks on five embassies in Bangkok and two Thai beach resorts, arresting three Thais and one Singaporean.
Intelligence analysts say it was only a matter of time until a larger plot was hatched in Thailand, particularly as targets in Indonesia, the Philippines, and Singapore have all gotten "harder" since officials revealed various plots in those countries.
The arrests also underscore the regional nature of JI - the group behind the Bali attack - and how the Wahhabi ideology it shares with Al Qaeda has spread beyond ethnic and national lines. Like the group led by Osama bin Laden, which is thought to have members from more than 35 countries, JI has shown it can move beyond its base membership, drawn from Indonesia.
"This is quite worrying because it indicates the JI have penetrated communities that we thought wouldn't be so easy,'' says Andrew Tan, a political scientist at Singapore's Institute for Defense and Strategic Studies. "JI has people of many ethnic backgrounds, which is a characteristic of Al Qaeda - in a way, the JI seems to be a mini-Al Qaeda in Southeast Asia."
Though nothing like the conflicts in neighboring Indonesia or the Philippines, resentment against Thailand's Buddhist majority has occasionally led to antigovernment violence. Now the government must contend with the presence of a regional terror network.
Details are slowly emerging about the substance of the plan. Minister Wan said it was for "high-powered explosives to be concealed in vehicles at the targeted places," and he indicated there would have been simultaneous explosions - something that has been a hallmark of Al Qaeda and JI.
"The investigation shows connections (to JI),'' Thailand's Interior Minister Wan Mohammad Noor Matha told reporters on Wednesday. "There is something to indicate that there was a plan to carry out attacks."
Key to the discovery of the Thai plot was Singaporean Arifin bin Ali. Unlike the minority Malay community that Singapore's JI members have been drawn from, Mr. Ali is a member of the dominant ethnic-Chinese and a convert to Islam.
The Singapore government says he learned how to handle guns and build explosives at a Moro Islamic Liberation Front camp in the Southern Philippines in 1999. And when Singapore discovered the existence of JI and arrested two dozen terrorist suspects in December 2001, he fled through Malaysia to Thailand, where contacts were in place to help him hide.
Mr. Ali was arrested in Bangkok in the middle of May, on a tip provided by Singapore intelligence. That information from Singapore followed the arrest of Mas Selamat Kastari, the leader of the cell Ali had belonged to before fleeing Singapore. Mr. Kastari, in turn, was arrested in Indonesia.
The arrest of Ali helped uncover the plan to bomb the embassies in Bangkok, and led to the three Thais arrested on Tuesday. The three suspects are Maisuri Haji Abdulloh, the leader of an Islamic school on Narathiwat, his son Muyahi, and an associate Waemahadi Wae Dao.
Mr. Tan says there were undoubtedly more conspirators, and expects more arrests to be made soon. "This should not be seen as an overwhelmingly significant victory. Of the 400-500 estimated JI operatives, how many have been caught? The overwhelming majority are still at large."
Perhaps the most important Jemaah Islamiyah operative, Riduan Isamuddin, has avoided arrest for over three years.
Mr. Isamuddin, who's better known as Hambali, fought alongside Osama bin Laden and is thought by Southeast Asian and US investigators to be a full-fledged member of Al Qaeda. He's been on the run since coordinating attacks on 17 Indonesian churches on Christmas Eve 2000.
Hambali has also been tied to fatal bomb blasts in Manila, the Philippines ambassador's house in Jakarta, and the Bali attack, which killed 202 people, mostly young tourists, at two Bali nightclubs last October.
With its porous border in the south and relatively laissez faire attitude toward JI, Thailand has for years been a key meeting place for the group. In 2002, Hambali, the Bali attack coordinator Ali Ghufron alias Mukhlas, and key financier Wan Min Wan Mat all hid out in Thailand.
According to the US interrogation of Mohammed Mansour Jabarah, an alleged Al Qaeda member, Hambali led a meeting in Bangkok in January 2002 at which JI decided to shift its focus to soft targets such as nightclubs, following a failed plot to attack embassies in Singapore.
Mukhlas, currently on trial for the Bali attack, told the Indonesian police that $15,000 used for the Bali attack was given to him by Wan Min, a Malaysian national, in the southern Thai town of Yala in March 2002.
Thailand's convenience as a place to make plans had led some analysts to conclude that it probably wouldn't be targeted for an attack - as that would likely deprive the group of its last comfortable spot in the region.