Four including an Indian escape from Bali prison

Shaun Edward Davidson, from Perth, was serving a 12-month sentence after being convicted in September past year of using fraudulent travel documents.

Davidson was one of four prisoners who escaped through a tunnel they dug underground.

Four foreign nationals have escaped the Bali's Kerokoban Prison using a tunnel, the Indonesian police are searching for the prisoners.

Davidson had just two months and 15 days left to serve of his sentence for immigration offences after he was caught in April previous year for using another man's passport on the popular tourist island. "Maybe we should change the law", he said.

"We will investigate if there's involvement from other prisoners or guards", Mr Nainggolan said, with police adding that they were also looking into whether the men received any help from the outside.

Prison governor Tonny Nainggolan admitted authorities never suspected the cement cover near the jail's clinic disguised an escape tunnel.

They are believed to have escaped through a 50cm by 70cm hole found in the outer wall which connects to a 15m-long narrow tunnel, according to prison officials.

Davidson said he lost his passport.

Police identified the four as Australian Shaun Edward Davidson, 33, Bulgarian Dimitar Nikolov Iliev, 43, Indian Sayed Mohammed Said, 31, and Malaysian Tee Koko King bin Tee Kim Sai, 50. He fled Perth for Bali after being charged with drug offences. He was arrested in April 2016 after he signed into a guest house in Kuta under the name Michael John Bayman from a passport. It gives them something to look forward to.

Davidson had spent the year before he was apprehended boxing and partying.