Jakarta, Indonesia - Indonesian police tightened security across the country after finding three bombs set to go off, following word of the imminent execution of a trio convicted of the 2002 Bali bombings that killed 202 people.

A source at the Nusakambangan island prison off southern Java said ringleader Imam Samudra, 38, Amrozi Nurhasyim, 47, and his brother Mukhlas, 48, had been placed in isolation in preparation for their date with the firing squad.

'The letter ordering the execution was submitted last night at 9pm (10pm Singapore time on Friday),' the source said. He did not say whether the letter gave a precise time.

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