A Melbourne man has been placed on Interpol's most wanted list after allegedly committing war crimes during the breakdown of the former Yugoslavia.

A Croatian public state prosecutor claims Predrag Japranin was responsible for the murders of three people in the Croatian town of Petrinja in November 1991.

A Croatian woman, Kristina Siftar, told 7.30 Mr Japranin, a Serb, came to her home and took away her son, Marijan, and another man, Milan Krnjaic.

The two men's bodies were found five years later in a mass grave, along with the remains of the third man Mr Japranin is alleged to have murdered, Branko Kovacevic.

It is alleged Mr Japranin was a member of a Serb militia, formed when Croatia declared independence from Yugoslavia in 1991.

Serbs in the region around Petrinja declared their own mini-republic, Serbian Krajina, and held it until 1995 when the Croatian government reasserted its control over the area.

Mr Japranin, who arrived in Australia in 2000 and is now an Australian citizen, refused to be interviewed on camera, but told 7.30 he was innocent of the charges, had never been to the Siftars' house, and never served in a militia group.

However, documents left behind by Serbs when they fled in 1995 list Mr Japranin as having served in a unit of the Serbian Krajina military.

A former Croatian army colonel and war historian, Ivica Pandza, told 7.30 the unit was deployed to capture Croats for information.

Mother recalls last time she saw her son

Mrs Siftar said she had known of Mr Japranin before the war and that she recognised him when he came to her house with another man because he was missing his right hand.

She said he told her her son and his friend, Milan Krnjaic, had to come with him as he was supposed to take them to the local brickyard, where Serbs were holding and questioning Croats.

Mrs Siftar waited until the next morning and went to the brickyard, but the Serb in command there told her Marijan and Milan had never been there.

When the Croatian army reoccupied the area, a number of mass graves were found, including the one containing the bodies of Mr Japranin's three alleged victims.

Many people fled seeking sanctuary

Many Serbs fled the region ahead of the Croatian forces, seeking sanctuary in Serbia, Montenegro, the Bosnian Serb Republic and other countries.

After the war, a Croatian court heard evidence about the murders and issued a warrant for Mr Japranin's arrest and an indictment.

As recently as 2012, a court in Zagreb called for him to be returned and imprisoned while he stood trial.

In order for Mr Japranin to stand trial, the Croatian government would have to ask Australian authorities to arrest and extradite him.

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