A man has been arrested in Italy over the notorious alleged murder of two housemates in inner-city Melbourne almost half a century ago.

Nearly five decades since the murders of Suzanne Armstrong and Susan Bartlett, a man has been arrested in Italy and Victoria Police are seeking to extradite him.

One of Melbourne’s oldest inner-city schools is the link connecting Perry Kouroumblis to the 1977 Easey Street murders.

The crime, known as the "Easey Street murders," became Melbourne's longest and most serious cold case, but no one had been arrested until now.

Police had told Suzanne Armstrong’s sister Gayle years ago that they wouldn’t give up on the murder case. So she didn’t either, always hoping a breakthrough might come.

A man has been arrested over the brutal murder of two women after a police investigation that spanned nearly five decades and multiple continents.

The sister of one of the women killed in one of Victoria's most infamous cold cases has said she always knew an arrest would one day be made. A man was arrested in Italy as part of the investigation into the 1977 murders of Suzanne Armstrong and Susan Bartlett at their home on Easey Street,