Terrorists, like smugglers and pirates, tend to congregate in geographical backwaters.
The arrest of an alleged terrorist leader Sunday night on Indonesia's Bintan island near Singapore is shedding light on how easily local maritime borders have been exploited by groups tied to Al Qaeda - and the progress that Southeast Asia's governments here are making in bringing them under control.
Mas Selamat Kastari was caught more than a year after he went underground with the other members of his five-man Jemaah Islamiyah (JI) cell. The JI has been blamed for the Bali nightclub attacks that killed 190 people last August and a string of lesser attacks in Southeast Asia dating back to 1999.
Mas Selamat, a JI cell leader, had been enraged by the arrest of other alleged JI members in 2001 and was planning to hijack an airliner and crash it into the city's Changi Airport, say Singapore officials.
Instead, an informant tipped off investigators about his cell's existence and the group bolted to Indonesia through the Riau Archipelago just south of Singapore - the same island group famed for piracy and smuggling - where he was finally brought to ground.
Erwin Mappaseng, the head of Indonesia's police crime investigation division, told reporters the arrest was made thanks to intelligence provided by Singapore.
Mas Selamat is not thought to have participated in the Bali attacks. But the fact that Indonesia cooperated in the arrest, say investigators, is cause for cheer. Until now Indonesia, the world's most populous Muslim country, had been reluctant to move against alleged members of the network unless they had been involved in crimes on Indonesian soil. But all of Mas Selamat's activities were thought to be outside Indonesia.
"This is a significant arrest because it shows that Indonesia is finally willing to go after the broader network,'' says Rohan Kumar Gunaratna, a political scientist and terrorism expert. A Singapore government official praised "the close cooperation" with Indonesia in the arrest.
New evidence being uncovered by the investigations into the Bali blast - and the interrogations of alleged JI members - shows the Riau archipelago to be crisscrossed with the tracks of men tied to almost every major recent terrorist attack in the region. While officials have long known that money and ideas flowed freely around the region, they're now coming to see the ease with which JI operatives switched countries.
"This terror network has always been a regional terror network, and insufficient border controls helped it to grow,'' says Gunaratna.
Take Imam Samudra, the admitted field commander of the Bali attack. He made Batam island in Riau, next to Bintan, almost a second home before leading a bombing attack on four Batam churches on Christmas Eve 2000, according to his deposition by the Indonesian police, a copy of which was read by the Monitor. The Batam attacks were a subset of what, in hindsight, was the JI's deadly "coming out party" - 20 simultaneous attacks on churches in nine Indonesian cities that Christmas.
BATAM was an ideal site for planning the attack, because it was so easy to bring in outside expertise and support, Mr. Samudra told investigators.
For instance, days before the attack, two Singaporean JI members, Hashim bin Abas and Jafar bin Mistooki, hopped on the ferry to Batam to help Samudra's five-man team to prepare and plant the bombs, according to Samudra.
The two Singaporeans have been under arrest in Singapore since 2001 for participating in failed plots to destroy the US Embassy and other Western targets there, and to destroy the water pipelines that carry most of the island state's water from neighboring Malaysia. A Singapore official confirmed that "two of the men we have in custody are suspected of ties to the Batam attacks,'' but declined to comment further.
During the time of the Batam attacks, senior JI leaders dropped by to give pep talks and last-minute instructions to Samudra and his men, he told police. This was unusual behavior, since the group's leadership usually avoided contact with foot soldiers unless it was necessary. They may have seized the opportunity because they were stopping over on the island anyway on their way to Malaysia and Singapore, investigators say.
Samudra said the JI operations head Riduan Isammudin, better known as Hambali, stopped in Batam's Century 2000 Hotel that December to "bring motivation for the attack." Ali Ghufron, who's better known as Mukhlas and who served as the operations head for the Bali attack, also came to Batam to bring last-minute instructions, according to Mukhlas's Indonesian police deposition.
Both Hambali and Mukhlas provided the key bridges between Jemaah Islamiyah and Al Qaeda. Both men fought the Soviet Union in Afghanistan as members of Osama bin Laden's International Brigade in the late 1980s, and both had personal contact with Mr. Bin Laden, according to police investigators. Hambali remains at large.
Bintan and Batam are sometimes seen by Singaporeans as their Indonesian backyard, where they go for golfing holidays, mountain biking, cheap seafood, and much cheaper factory labor than can be had in the wealthier city-state. The two islands are also one of the most popular crossings for the thousands of Indonesian workers who cross into Malaysia looking for work every week, both legally and illegally, so it's no surprise these islands provided such easy passage.
They're filled with quiet coves and small fishing boats that make illegal crossings easy, though the terrorist network's operatives usually moved through official frontiers, counting on a combination of poor computerization and official corruption to keep them safe.
Almost every major alleged JI operative in the region has passed through the islands at one time or another. Samudra was heading to Tanjung Pinang, the city on Bintan where Mas Selamat was arrested, when he in turn was arrested in November last year. Omar al- Faruq, a Kuwaiti national and alleged bridge between JI and Al Qaeda who was abducted by Indonesian intelligence and handed over to the US in the middle of last year, was in Tanjung Pinang shortly before his arrest.
Review of police documents and interviews with investigators show that the Riau archipelago is just one of three principal transit points for men, money, and weapons involved in Southeast Asian terrorism.
Sidney Jones of the International Crisis Group points out that the border between Indonesia and Malaysia in eastern Borneo, and the island of Sulawesi, which has traditional trading links with the southern Philippine island of Mindanao, where JI operatives have gone for training with Muslim separatists, have also been crucial conduits.
What all three locations have in common is frequent ferry service, lax border controls, and corruption. "The answer to terrorism is going to require more cooperation in controlling border crossings,'' says Gunaratna, the terrorism expert.