THE disclosure that Mas Selamat Kastari was plotting against Singapore while on the run did not surprise terrorism experts but they doubt that he had gathered enough resources to launch a large-scale operation.

Ms Sidney Jones of the International Crisis Group, who has closely tracked extremist groups in the region, said a critical mass of people is key.

'You can't just carry out an attack by yourself even for somebody who is a committed suicide bomber. You need people to do the surveying, to help prepare materials and to be look-outs.'

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