A British paedophile has been interviewed by police in his jail cell in Malta about the disappearance of Madeleine McCann in 2007.
Roderick MacDonald, 77, was quizzed as part of Operation Grange by Scotland Yard detectives.
They wanted to know about MacDonald's links to a paedophile ring which was active in Portugal and has been linked to Madeleine's disappearance.
A former friend of MacDonald revealed he boasted about his time in the Algarve area.
"He was always talking about how he was in the Algarve when Madeleine went missing," they said.
"He would brag about how he sailed a yacht into Praia da Luz but we never thought anything of it.
"We had no idea how evil this man was before he was arrested. Now it seems completely sinister. No wonder the police were so keen to quiz him."
Police officers had planned to speak with MacDonald in Britain, but that changed after he was jailed in Malta over child sex abuse images discovered on his computer.
News of MacDonald's interview comes as officers gear up to question more people in Portugal, next week.
Eleven people, including seven who are suspects known as "arguidos", will be interviewed.