Bali Nine Australians Chan and Sukumaran moved to execution site

The ringleaders of the "Bali Nine" Australian drug gang are being transferred from Bali to another Indonesian island to be executed.

Andrew Chan and Myuran Sukumaran are among 11 foreigners expected to face a firing squad in the coming days.

Australia has pressed Indonesia not to go ahead, with Prime Minister Tony Abbott saying he was "revolted".

The pair were convicted in 2005 after being caught attempting to smuggle heroin from Bali to Australia.

Indonesia has some of the toughest drug laws in the world and ended a four-year moratorium on executions in 2013.

President Joko Widodo has said the drugs trade destroys lives in Indonesia and he will show no mercy to convicted dealers.

'Terrible crime'

Chan and Sukumaran left Kerobokan jail in Bali in the early morning in armoured cars and are being transferred to Nusakambangan, the prison island where the executions are due to take place.

The BBC's Karishma Vaswani in Jakarta says while the move has not been officially confirmed by prison authorities it was expected, and appeared to have been carried out early in the morning to avoid media attention.

It is not clear when the executions will take place, but a formal announcement will be made by authorities 72 hours before, our correspondent adds.

Chan's brother Michael and Sukumaran's mother Raji, who have visited the pair regularly, were seen talking with prison guards after the convoy left.

Australian media said they were refused a request to see the pair.

Speaking to ABC News on Wednesday, Mr Abbott said millions of Australians were feeling "sick in their stomachs at the thought of what's likely to happen to these two men".

He acknowledged that they had "committed a terrible crime", but added: "We abhor the death penalty, which we think is beneath a country such as Indonesia."

Chan and Sukumaran are being transferred with two other foreigners facing execution - a 45-year-old Nigerian man and a 30-year-old woman from Spain.

Who are the Bali Nine?

• The eight men and one woman were arrested in April 2005 at an airport and hotel in Bali, Indonesia after a tip-off from Australian police.
  
• They were trying to carry 8.3kg (18lb) of heroin back to Australia
  
• In 2006 a court ruled that Andrew Chan and Myuran Sukumaran had recruited the others and paid their costs. They were sentenced to death
  
• The other seven are serving sentences of between 20 years and life, after some had death sentences revoked on appeal
  
• Chan and Sukumaran have repeatedly appealed against their sentences and say they are reformed characters - Chan teaches Bible and cookery classes in prison while Sukumaran is an artist
  
  

Who are Chan and Sukumaran?

Chan and Sukumaran's relatives and supporters have pleaded for their lives to be spared, arguing that they have been rehabilitated while in jail.

Lawyers for the two men said they were still attempting to mount a legal challenge but Indonesia's Attorney General Muhammad Prasetyo said on Monday that any legal appeals were no longer valid following the earlier rejection of clemency by President Widodo.

Earlier in the month, all of Australia's living former prime ministers made a united plea for Indonesia to spare the lives of Chan and Sukumaran.