Merauke – Five Australians jailed for illegally entering Indonesia's sensitive Papua province by plane have been released after winning their appeal, their lawyer said Tuesday.

They will fly the plane home as soon as Tuesday after the high court ruled that they had received verbal permission to land from the control tower in Papua's Merauke district on Sept. 12, their lawyer said.

A lower court in January jailed them for up to three years. They had flown from Horn island off northeastern Australia on what they described as a sightseeing trip.

"They have all been freed since the high court accepted their appeal on March 5," lawyer Efrem Fangoihoy said. The court had yet to make its ruling public but the lawyer said he was expecting formal notification later Tuesday.

"The judges accepted our arguments that the pilot decided to land as the tower official gave verbal permission despite the pilot's explanation that they hadn't obtained landing permit documents," he said.

"The conversation between the pilot and the tower official in Merauke's airport had been recorded and we gave a copy to the court."

He said that even if they hadn't obtained clearance to land, the most the Indonesian authorities could do was deport them for not having visas.

The Australians – pilot William Scott-Bloxam and his wife, Vera, plus Hubert Hufer, Karen Burke and Keith Ronald Mortimer – are expected to leave Papua as soon as they receive formal notice of the court's decision.

A low-level separatist insurgency simmers in Papua and the province remains one of the most sensitive areas in the vast Indonesian archipelago.

Journalists are banned from visiting Papua without special permission and the military is accused of human rights violations there.