Scotland Yard police investigating the 2007 disappearance of Madeleine McCann have flown to Malta to quiz a convicted sex offender believed to have been at the Portugal resort where she was last seen.

According to the Daily Mirror, British officers flew to Malta this week to question Roderick MacDonald in his prison cell about his alleged connection to a child sex gang operating in Portugal that has been linked to Madeleine’s disappearance.

MacDonald, 77, was expected to be extradited to the United Kingdom, the paper reported, but when Maltese detectives searched his apartment they found child pornography. MacDonald was then sentenced to 16 months in prison, forcing the British police to fly to Malta.

MacDonald served a six-month jail sentence for sexually assaulting an 8-year-old in 1998 and was convicted of molesting two girls, ages 5 and 7, on a boat in 2012.

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He was expected to be pressed on his knowledge about a string of burglaries that occurred at the Praia da Luz resort in Portugal, where Madeleine’s family was staying when the then-3-year-old vanished on May 3, 2007.

Detectives believe the burglaries -- reportedly carried out by a lone intruder between 2004 and 2010 -- are key to learning what happened to Madeleine.

A friend of MacDonald’s told the Mirror that he had no idea about MacDonald’s history as a sex offender, but that “he was always talking about how he was in the Algarve when Madeleine went missing.

"He would brag about how he sailed a yacht into Praia da Luz but we never thought anything of it.”

The grilling of MacDonald comes as 11 people are expected to be questioned next week over Madeleine’s disappearance. They will be interviewed at witnesses, not as suspects.