'The terrorism situation in Southeast Asia is under control, but the threat is far from over,' he said in his first remarks on the re-capture of the Singapore Jemaah Islamiah (J) terror leader by Malaysian Special Branch in Skudai, Johor Baru, on April 1, after being on the run for over a year.

PM Lee said for every attack reported in the newspapers there are many more plots which the security agencies uncover, track and hopefully disrupt.

'These never make it into the public consciousness, but we know about them from intelligence reports,' he said in a statement commenting on the Mas Selamat's arrest, which was reported by The Straits Times on Friday, and confirmed by Singapore and Malaysian home ministers on the same day.

'Our challenge is to keep up our guard without getting fatigued or complacent. The price of security is eternal vigilance.'

Mr Lee said the JI group remains active in the region, which must work together to counter them as well as other such groups.

This was a point he made to Malaysian Prime Minister Najib Razak at a four-eye lunch in Pattaya on April 11, after the Asean summit was called off because of the 'Red Shirt' demonstrations.

During the meeting, Datuk Seri Najib told Mr Lee that the Malaysian authorities had nabbed Mas Selamat, whose escape from the Whitley Road Detention Centre on Feb 27 last year sparked the biggest manhunt in Singapore's history and prompted Interpol to issue a global security alert.

Mas Selamat fled Singapore by swimming across the Johor Strait with the help of an 'improvised flotation device,' said Deputy Prime Minister Wong Kan Seng at a media briefing on Friday. He said Singapore government was informed of the arrest 'soon after' the fugitive was caught, adding that the arrest is the result of the strong co-operation between security agencies on both sides.

In his statement on Saturday, PM Lee said he told Datuk Seri Najib that he especially appreciated the close cooperation and trust between ISD and the Malaysian Special Branch, and thanked Malaysia for its generous support and help.