The execution of the three Bali bombers appeared imminent Wednesday as wooden posts to secure them for the firing squads were erected on their prison island, an official source said.

Senior Indonesian Islamic clerics also said they been asked to visit the Islamist militants in their isolation cells on death row, to provide final spiritual counselling.

The official source said three wooden posts had been erected 16 feet apart, 3.7 miles south of the high-security prison on Nusakambangan island, southern Java, where the bombers are being held.

Two Nigerian drug traffickers were executed in the same area in June.

Officials have said only that the bombers — Imam Samudra, 38, Amrozi, 47, and his brother Mukhlas, 48 — will be shot in "early November."

The bombings of packed nightspots on the resort island of Bali in 2002 killed more than 200 people, mostly foreign tourists including 88 Australians, as well as 38 Indonesians.

Executions in Indonesia are carried out by firing squad in the dead of night at undisclosed locations. The prisoners are usually informed at least three days before.

Sahlan Natsir, a member of the local Islamic clerical body near the prison, said he was preparing to go to the jail to counsel the bombers before they die.

"We have received a letter from the Cilacap prosecutor's office to send nine clerics to the prison to provide counsel for the trio,'' he said.

The letter did not specify when the clerics would be asked to visit the condemned men, who are said to be calmly awaiting death after being placed in isolation on Friday.

They are reportedly impatient to become "martyrs'' for the Islamic utopia they dream of creating across South-East Asia.

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