Madeleine McCann may have been abducted by slave traders and sold to a rich family, a former policeman has claimed, amid reports of a possible sighting.

Almost 10 years after the three-year-old girl vanished while the family were on holiday in Portugal, private detectives hired by the McCanns reportedly believe she may have been smuggled by ferry into Africa.

Gangs in Mauritania, West Africa, are known to sell youngsters to wealthy Middle Eastern families.

Colin Sutton, a former Scotland Yard detective, told the Mirror: “The Mauritania line is certainly a possibility and needs to be looked at.