Australian police charged a man on Tuesday with the murder nine years ago of a male sex worker who claimed to be a vampire and who had allegedly raped a woman and bitten off part of her tongue.

Shane Chartres-Abbott, 28, was gunned down in broad daylight in front of his pregnant girlfriend in an ambush outside his suburban Melbourne home in June 2003 in what was thought to be a professional hit.

Chartres-Abbott, a prostitute, was about to face trial at the time, accused of raping a female client and biting off part of her tongue after allegedly telling her he was a 200-year-old vampire who drank blood to survive.

He pleaded not guilty in the case, arguing he was the victim of a counter-plot in which he was being secretly groomed by the woman for a "snuff movie" that was to end with his death.

Police said they had made a "significant breakthrough" with the Tuesday arrest of Warren Shae, 40, who they have charged with murder.

"The charge follows a lengthy and difficult investigation by Victoria Police, assisted by the Australian Crime Commission," police said in a statement.

They have offered an Aus$1 million (US$1.58 million) bounty for the man suspected of arranging the hit, Mark Adrian Perry, who is believed to have fled to Thailand in 2009 after learning he was wanted for questioning.

Perry's disappearance had "further complicated" the case but they were now confident that further arrests would follow, police said.

"It was a very vicious and nasty rape, there's no question about that, but a murder of a person facing court for that particular rape offence just rocks the justice system," said assistant police commissioner Jeff Pope.

"We just can't have summary justice occurring in our society."