MELBOURNE, Australia (AP) -- Five Australians who had spent almost 20 years in Indonesian prisons for heroin trafficking returned to Australia on Sunday under a deal struck between the two governments, Prime Minister Anthony Albanese said.

The governments confirmed weeks ago that negotiations were underway for Matthew Norman, Scott Rush, Martin Stephens, Si Yi Chen, and Michael Czugaj to be returned to Australia. Their return on Sunday was shrouded in secrecy.

There was uncertainty about whether they could potentially serve out their life sentences in Australian prisons. However, Albanese confirmed in a statement Sunday the men returned to Australia as free citizens.

He also thanked Indonesian President Prabowo Subianto for the men's release.

"Australia respects Indonesia's sovereignty and legal processes and we appreciate Indonesia's compassionate consideration of this matter," Albanese said.

The five were among a gang of nine Australian smugglers arrested in the Indonesian tourist island of Bali in 2005 as they attempted to smuggle 8.3 kilograms (18.3 pounds) of heroin strapped to their bodies to Australia.

Two convicted ringleaders of the Bali Nine, Andrew Chan and Myuran Sukumaran, were executed by a firing squad in 2015, causing a diplomatic furor between neighbors Indonesia and Australia. One of the drug smugglers, Tan Duc Thanh Nguyen, died of cancer in prison in 2018, while Renae Lawrence, the only woman in the group, was released and returned to Australia the same year.

Indonesia's senior law minister, Yusril Ihza Mahendra, said the five flew on the Australian airline Jetstar on Sunday from Bali's Ngurah Rai International Airport to the northern Australian city of Darwin, with no media presence.

Mahendra also said their repatriation came after he and Australian Minister of Home Affairs Tony Burke signed a "Practical Arrangement" on Dec. 12 in a virtual meeting to send back the five traffickers.

He added that the men had not been pardoned by the Indonesian president and were transferred as "prisoners," but "once repatriated," they became the responsibility of the Australian government.

Australia's government had offered the five temporary accommodation, medical care and any other support required, local media reported.

Albanese said they will "have the opportunity to continue their personal rehabilitation and reintegration here in Australia."