Security experts said the capture of Mas Selamat Kastari was important as it showed cross-border cooperation and scotched any moves to hook up with militants in Indonesia to plan attacks such as the one that killed more than 200 in Bali in 2002.
Singapore, a center for Western businesses and finance, said the capture did not mean it could let its guard down.
We must not assume that the arrest of one person means Singapore is safe from terrorist threat, said Singapore Deputy Prime Minister Wong Kan Seng on state television. We must continue to be vigilant.
He said Mas Selamat reached Malaysia by using an improvised flotation device from Singapore's north shore, after escaping from prison. Mas Selamat was captured in Malaysia's Johor state on April 1, across a narrow strait from Singapore, intelligence sources told Singapore's Straits Times newspaper.
He was planning something, which allowed us to arrest him, said Malaysia's Home Minister Hishammuddin Hussein at a press conference. We are becoming an expert on him. Hopefully, this time he will not escape us.
Officials have said Mas Selamat was a leader of the Singapore cell of Jemaah Islamiah (JI), a pan-Asian radical Islamic group linked to al Qaeda and responsible for several attacks across Southeast Asia, including the Bali bombings.
He was also the alleged mastermind of a plot to hijack a plane and crash it into Singapore's Changi Airport.
Additionally, Singapore authorities accuse him of planning truck bomb attacks at several sites across the island state, including the American Club and U.S. Embassy. He has not been formally charged with any crimes and was held under Singapore's Internal Security Act, which allows for detention without trial.
Experts say JI's ability to carry out attacks is waning after several high profile arrests, but thousands accompanied the bodies of the Bali bombers to their burial last year, showing sympathies remain among some in Indonesia for militant Islam.
I don't think that Singapore has been at risk of an attack for a long time. What we were worried about was whether Kastari would join forces in Indonesia, said Sidney Jones, a JI expert at International Crisis Group in Jakarta.
His escape through the toilet window of a detention center in Singapore in February 2008 sparked a huge manhunt and an Interpol alert.
The escape, in which Mas Selamat tricked guards while changing and fled without his trousers, was highly embarrassing for Singapore.
Singapore sacked or disciplined several officials but no ministers resigned, and the government came under fire from internet bloggers as army gurkhas combing forests and photo posters all over Singapore failed to unearth Mas Selamat.
I am glad that he has been recaptured but the fact he was captured by Malaysian police showed how porous our borders are, said Ernest Teng, an advertising sales manager in Singapore. It can also mean other like-minded individuals like him can come into Singapore undetected too.