As recently as last week, the head of the respected think-tank International Crisis Group told an audience in Australia that the al-Qaeda-linked group Jemaah Islamiyah was no longer a serious threat in Indonesia or elsewhere after a clampdown by authorities.

"The JI regional division that covered Australia has been effectively smashed by Indonesian police and intelligence operations, well supported by Australian agencies," the head of the ICG, former Australian foreign minister Gareth Evans, said.

"JI itself no longer poses a serious threat in Indonesia or elsewhere," he added.

That was, of course, before the three apparent suicide bombers blew themselves up in packed restaurants on the Indonesian holiday island. They killed at least 26 people, three of them Australians, and wounded scores.

And JI was the group immediately blamed.

"The only group that has the intention and capability to mount a coordinated and simultaneous attack against a Western target in Indonesia is Jemaah Islamiyah," Rohan Gunaratna, head of terrorism research at Singapore's Institute of Defence and Strategic Studies, told AFP hours after the attack.

The blasts bear all the hallmarks of a JI operation, said Ansyaad Mbai, head of the anti-terrorism desk at Indonesia's security ministry, Jemaah Islamiyah, whose name means "Islamic community", has staged more than 50 bombings or attempted bombings in Indonesia since April 1999.