Authorities had been searching for several suspects over the shooting of Zivan Radmanovic, a 32-year-old Australian national, on Saturday.

He was killed when two people burst into his villa in the tourist hub of Badung and at least one opened fire. A second man, 34-year-old Sanar Ghanim, was seriously wounded in the attack.

"Three suspects have been arrested along with several pieces of evidence allegedly used to carry out the shooting," Bali police chief Insp. Gen. Daniel Adityajaya told reporters.

He said the three suspects -- all Australian men -- were charged with multiple offences, including premeditated murder, which carries a maximum penalty of death, as well as murder and torture resulting in death.

Murder carries the maximum penalty of 15 years in prison, while torture resulting in death carries a potential seven-year jail term.

One of the suspects was detained while he was about to leave the international airport in Jakarta and flown back to Bali, in cooperation with immigration and national police officials, he said.

"The other two already fled and were successfully returned because of the coordination between interpol countries in the Southeast Asia region," he added, without specifying the countries involved.

He did not disclose the alleged role of the third suspect, despite the search initially focusing on two suspects.

They also seized items such as a 9-mm gun, a motorcycle and two cars the suspects had used to flee the scene of the crime, Adityajaya said. 

Police have not given a motive for the crime, saying their investigation continues, with Adityajaya adding that a further suspect could be identified as the plot's mastermind.

Bali police also showed on Wednesday several pieces of evidence to the media including a hammer, several pieces of clothing, and bullet casings.

Witnesses, including Radmanovic's wife, said the perpetrators who fled the scene after the attack were speaking in English with a thick Australian accent, according to a local police statement.

The Australian embassy in Jakarta directed questions to the Department of Foreign Affairs and Trade, which did not immediately respond to an AFP comment request.

Gun crime on the island of Bali and wider Indonesia is rare, and the archipelago nation has strict laws for illegal gun possession.