Goncalo Amaral, the police officer who first lead the investigation into the three-year-old British girl’s disappearance in Portugal, claims police are looking into a "German paedophile who is in prison."
Dubbed the "masked man" Martin Ney, 48, was jailed for life in 2012 for "abducting and murdering three children, and sexually abusing dozens more," The Sun reports.
The publication reports that the youth worker "dressed in black and donned masks and balaclavas while carrying out his attacks" in Germany, France and Holland, and knew the Praia da Luz area where Madeleine was staying with her family well.
He reportedly confessed to killing three German children and sexually abusing 40 other minors before he was imprisoned for life.
WATCH: POLICE MAKE STATEMENT IN THE SEARCH FOR MADELEINE MCCANN