The international dragnet is now turning up new evidence of Asian links to Osama bin Laden's Al Qaeda organization, underscoring the breadth of his operations.
A captured Philippine rebel leader on Monday named Mr. bin Laden as a financier of Abu Sayyaf, a Muslim fundamentalist group. The Abu Sayyaf has been holding a US missionary couple and 16 Filipinos hostage for several months.
Muslim Malaysia pledged cooperation in fighting terrorism as it came under scrutiny over a report that one of the hijack suspects in the airliner that hit the Pentagon had been caught on a surveillance tape in Kuala Lumpur, meeting a man linked to bin Laden.
About a dozen followers of bin Laden, suspected of having masterminded last week's devastating attacks on New York and Washington, may have entered Japan from Pakistan just days before the assault.
Days before the Sept. 11 plane-hijacking assaults, police in the Philippines took three men "of Middle Eastern origin" in for questioning, after they were found videotaping the US Embassy in Manila.
Bin Laden's long-standing ties to Islamic fundamentalist and separatist groups in countries including Indonesia, the Philippines, Malaysia, and Singapore are bringing the global investigation into last week's grand-scale terrorism into the heart of Southeast Asia.
In a developing region where many trouble spots are defined - at least in part - by Muslim-Christian tensions, Muslim resentment of domination by pro-Western governments, and political or territorial secessionism beneath the banner of Islam, several Southeast Asian groups have in the past been open about their connections, at the least, with the same ideological and territorial ground as bin Laden.
From the Abu Sayyaf ("master of the sword") extremists in the southern Philippines to the Laskar Jihad in Indonesia, the leaders of several of the region's Islamic militias received training in Afghanistan, as mujahideen fighting Soviet occupation forces in the 1980s.
All of Asia's leaders - including reclusive North Korea - condemned the massive loss of life in Tuesday's attacks. But the leaders of countries with large Muslim populations, such as Indonesia and Malaysia, appear to be shying away from support for massive military retaliation. Even pro-American Thailand warned yesterday that the US should not "jump the gun" on its response, until investigators can ascertain who is responsible.
Meanwhile, the ripple effects of last week's harrowing assaults are being felt across Asia, where US citizens and military personnel are on high alert amid continuing fears of follow-up or reprisal attacks. In Macau, a Portuguese-ruled enclave that reverted to Chinese control in 1999, government officials have arrested five Pakistani nationals. They reportedly
had, in their luggage, instructions to hit American targets in Macau and Hong Kong if US forces launch attacks on Afghanistan.
The US consulate in Hong Kong, which has jurisdiction over Macau, closed indefinitely yesterday. No officials could be reached to confirm whether those detained were linked to bin Laden.
But seemingly few goings-on in Asia at the moment are not. In Tokyo, securities officials are investigating reports, which surfaced on Friday, that investors working on behalf of bin Laden engaged in massive short-selling of stocks and futures contracts before the attack. Such trades could have brought huge profits.
Political experts and security officials say that while it would be wrong to try to link every Muslim militant group in the region with bin Laden, it would be equally foolish to overlook the likelihood that he has given more to this part of the world than religious inspiration.
"Even though the term now is war and not law, there is a term - 'link' - which implies [a] smoking gun. But if Al Qaeda is as amorphous as we are led to believe, the connection to bin Laden may not be quite as clear as one might wish," says Donald Emmerson, an expert on Southeast Asian politics at Stanford University in Stanford, California.
Some of the region's militia leaders wear the fact that they learned to fight in Afghanistan as a badge of pride, and may have come to know bin Laden there. But whether or not that translates into ongoing financial or logistical support remains unclear.
On one hand, groups such as secessionists in Aceh, Indonesia, have limited their efforts to a battle against the government, leading some experts to conclude that their goals are largely local. On the other, various visits in the past two years - bin Laden's brother to Jakarta, the reported presence of one of the US hijackers at a meeting in Malaysia - point to possible closer ties.
"There is a likelihood that there are financial connections," Mr. Emmerson says. What is more likely, he says, is "tremendous sympathy, prior acquaintance, militant solidarity, previous knowledge."
But it is unclear whether a potential US attack against bin Laden would discourage or disable sympathetic Asian groups. "If we think that taking out bin Laden will solve the problem, that seems to me terribly naive," says Emmerson. "On the other hand, to absolve him and say this is all based on individual decisions by various groups, that is equally naive."
Security analysts in Jakarta say that over the past few years, radical Islamic groups, including bin Laden's network, have forged links with local extremists and infiltrated groups. Indonesia's creaky security forces and porous borders make it a potential staging ground for attacks on US targets.
Since late July, the US embassy in Jakarta has been on high alert after receiving a threat from an international Islamic group with links to bin Laden. "This wasn't local at all, it was definitely a foreign group," says a Western security analyst, who requested anonymity.
This week, Indonesia's new president, Megawati Sukarnoputri, will visit Washington and meet with President Bush. While the US leader will be looking for full backing for America's war on terrorism, that will likely put Ms. Megawati - once rejected by Indonesian Muslim groups as unfit to rule the world's most populous Muslim nation - in the hot seat.
"Southeast Asian Muslims are all saying that America must not overact, must not inflict suffering on innocent Muslims. And if they kill a sizable number of Muslims, that would provide quite a lot of backlash in countries like Malaysia and Indonesia," says Greg Fealy, an Indonesia expert at Australia National University in Canberra. "They're warning Megawati [that] Indonesia shouldn't be carried along by America's interests."
In Malaysia, many Muslims resent what they say is a leap to point fingers at Islamic groups. "It's a little too quick ... bouncing on Osama bin Laden, which is typical of American foreign policy," says Prof. Chandra Malaya, director of the Center for Civilizational Dialogue at the University of Malaya in Kuala Lumpur, Malaysia.
"This is the arrogance of power, which has always been the hallmark of US foreign policy," he says.
Material from the wire services was used for this report.