Hambali was 'plotting APEC attack'
Suspected mastermind of Bali, Jakarta attacks
Riduan Isamuddin, also known as Hambali.
Bush remarks on the capture of a key suspected al Qaeda member Riduan Isamabudian, known as Hambali (August 14)
CNN's Maria Ressa reports that al Qaeda has claimed responsibility for last week's bombing of a hotel in Jakarta, Indonesia. (August 11)
Three key Asian terror suspects are still at large following the arrest of Hambali.
Azahari Husin. A 46-year-old Malaysian former professor of statistics who studied in Britain and Australia. He is believed to have been the chemical brains behind the Bali bombing and the blast at Jakarta's Marriott Hotel.
Dulmatin. An Indonesian in his early 30s. Wanted for assembling the largest of the Bali bombs and for sending the text message to a mobile phone that set it off.
Fathur Rohman al-Ghozi, 32, is another Indonesian, a self-confessed Islamic militant and a top bomb-maker. He escaped on July 14 from a maximum-security detention center in Manila where he was serving a 12-year jail term for illegal possession of explosives.
WASHINGTON (CNN) -- The man accused of being the mastermind behind last year's Bali nightclub bombings may have been plotting to stage an attack on the upcoming Asian Pacific Economic Cooperation (APEC) summit, scheduled to be held in Thailand in October.
Riduan Isamuddin, known as Hambali, was arrested by Thai authorities two days ago in the central temple town of Ayutthaya, and was handed over to the CIA, according to senior U.S. officials.
Apart from the October 12 Bali blasts which killed more than 200 people, Hambali is also thought to be responsible for planning last week's explosion at the Marriott Hotel in Jakarta and possibly the September 11, 2001, attacks.
Investigators said Hambali was plotting to stage an operation during the APEC summit and that his arrest could possibly prevent some future attacks.
Thailand's defense minister said Hambali had been flown to Indonesia. But Indonesian officials said they had no knowledge on whether Hambali was in the country and said they weren't even informed of his arrest.
"We have not received any word about Hambali's extradition to Indonesia. Even the news of his arrest, we heard it from the press," Indonesia's national police spokesman Zainuri Lubis told CNN.
Indonesia does not have an extradition treaty with the United States and intelligence sources told CNN that if Hambali were to have been flown to Indonesia, he would not be staying there.
Hambali is the acting chief of Jemaah Islamiyah, a group that is basically a franchise of al Qaeda in Southeast Asia. He has served as a link between the groups, and was the only non-Arab to sit on al Qaeda's leadership council.
According to CNN's Maria Ressa, Hambali was sought by at least a half-dozen countries in the region for his suspected involvement in several bombings in various countries.
Sources told CNN al Qaeda had asked Hambali to recruit more suicide hijackers, and that an al Qaeda leader in Pakistan gave him a large sum of money earlier this year to carry out a major attack.
A senior administration official did not give a time or location for the possible future attack.
Administration officials called it a significant capture, and said they would interrogate him to cull information on future attacks.
U.S. President George W. Bush called Hambali "one of the world's most lethal terrorists" and said his capture was a significant victory in the war on terrorism.
"He is no longer a problem to those of us who love freedom," Bush told Marines at Miramar Marine Corps Air Station in California.
Australian Prime Minister John Howard welcomed the capture Friday, describing it as a "huge breakthrough".
"This man is a very big fish. He's the main link between al Qaeda and JI. He was almost certainly the ultimate mastermind of the Bali attack," Howard told Australian media.
"So to those relatives of the 88 Australians who died in that outrage almost a year ago, this is I hope some further measure of justice," he said.
"I congratulate the Americans and I'm sure that psychologically this capture will inflict a very heavy blow on the worldwide terrorist network."
Hambali has been blamed for the simultaneous bombings in 2000 in Malaysia and the Philippines, and with other terror attacks in the region.
A senior administration official said al Qaeda asked Hambali to recruit hijackers for other attacks after September 11, and he received large amounts of money for that mission.
Intelligence officials say Hambali may have helped plan the September 11 attacks by hijacked commercial airliners that killed nearly 3,000 people.
He was videotaped in January 2000 meeting with two of the hijackers in Malaysia -- Khalid Almihdhar and Nawaf Alhazmi.
The 38-year-old Afghan war veteran was part of a terrorist cell broken up by Philippine police in 1995. Three of its members are serving life sentences in U.S. prisons for a plot to bomb American planes in Asia.
They had begun recruiting pilots for suicide missions, to crash commercial planes into buildings like the Pentagon and World Trade Center.
Intelligence officials in the Philippines say they believe that the 1995 plan was the blueprint for September 11.
Al Qaeda leader Khalid Shaikh Mohammed, along with Hambali, evaded arrest in 1995 and moved further up al Qaeda's corporate ladder. Mohammed -- who was arrested in April -- became one of Osama bin Laden's trusted lieutenants, U.S. officials say. (Evidence found in his arrest, Mohammed's life)
There has been no comment from Indonesia on Hambali's capture.
Australia on Thursday warned that fresh terror attacks could be possible in Indonesia this Sunday, to coincide with the republic's national day.
Australia's Foreign Minister Alexander Downer said he feared a possible terror strike in the Indonesian capital Jakarta on August 17 targeting Westerners at "soft" targets such as shopping centers or international hotels. (Sunday warning)
The warning came one day after Australia's top spy chief said a "catastrophic" terrorist attack involving weapons of mass destruction was only a matter of time. ('Catastrophic' attack)
-- Journalist Amy Chew contributed to this report.