Authorities in Australia on Thursday said they've identified the remains of bushranger Ned Kelly, but the whereabouts of his skull are still unknown.

Kelly's skull was last thought to have sat on the desk of a Victorian state police detective in 1929.

The successful identification of Kelly's remains happened 131 years after he was hanged for murder. Scientists used DNA from Kelly's great great nephew, a Melbourne teacher, Leigh Olver, to identify his bones from others in a mass prison grave.

To think a group of scientists could identify the body of a man who was executed more than 130 years ago, moved and buried in a haphazard fashion among 33 other prisoners, most of whom are not identified, is amazing, Victoria's state Attorney-General Robert Clark said on Thursday.

Kelly is the Australian version of America's Jesse James. He was born around 1854 to an Irish convict who was banished to Australia. Kelly became a folk hero at a young age, as he fought against a corrupt British police force and robbed banks.

Kelly wore a homemade metal armor in a final shootout with authorities and he was shot, arrested and hanged in 1880 by the establishment he despised. He was hanged in Melbourne Gaol on Nov. 11, 1880 after being sentenced to death for murder over his gang's killing of three policemen.

Kelly's body was buried in the grounds of the old Melbourne Gaol and a death mask was made from his head.

The gaol closed in 1929, and Kelly's remains and the bones of other prisoners were exhumed and re-buried in a mass grave at the newer Pentridge Prison.

However, Kelly's skull may have somehow gotten separated from his skeleton during that transfer. The mass grave was dug up again in 2009, as researched began a quest to identify which of the bones belonged to Kelly.

It was doctors and scientists at the Victorian Institute of Forensic Medicine took a DNA sample from Oliver, Kelly's sister Ellen's great-grandson, who identified the remains.

The wear and tear of the skeleton is a little bit more than would be expected for a 25-year-old today, said institute director Professor Stephen Cordner. But such was Ned's life, this is hardly surprising.

Deputy Director of the Victorian Institute of Forensic Medicine David Ranson told Reuters that from a point of view of Australian culture there's always been this dichotomy of Ned Kelly the police killer and the folk hero at a time of unrest and tensions.

Ranson also said DNA now proves that a skull, which had been on display alongside the Kelly death mask at Melbourne Gaol, didn't belong to the bushranger.

Did that get lost in the transfer from prisons or was it souvenired? We don't know, he said.

Olver said there is relief now that there is finally some closure.

It's such a great relief to finally have this side of the story resolved, he told reporters.

He hopes that a suitable resting place could be found for his dead relative. 

A place of dignity, a place very appropriate, Olver said. Where that is will be determined later.

You can't just bury the man, Olver told The New York Times. Someone is going to dig him up again in half an hour.

But as they decide where is suitable to bury the villain, Australian police are now investigating a suspicious fire at a mansion once owned by Judge Sir Redmond Barry, who ordered Kelly's execution.

The Australian police announced the new investigation just one day after officials said they've identified the headless remains belonging to Kelly.

Victoria police issued a statement noting that the Saturday's blaze at the historic home in Melbourne seems to have been deliberately lit.

Police said the house was being renovated and that they believe vandals squatting at the home set the fire and may have stolen copper wire from the house.