Rare items including handwritten lyrics, art and collectibles from Mercury's London home, Garden Lodge, have been looked after by his close friend Mary Austin since his death from AIDS-related pneumonia in 1991.

The woman, a Korean-born New Zealander, arrived in South Korea in 2018 and had no record of departure since then, police say.

Police launched a homicide inquiry in Auckland after the remains were found by a family going through the contents of a storage locker they had purchased unseen.

The 40-year-old slab of marzipan and thick white icing decorated with the royal coat of arms fetched more than three times its asking price of £300 to £500.