Detectives have identified a German prisoner as a suspect in the disappearance of Madeleine McCann from Leicestershire.
The Metropolitan Police have not named the man, aged 43, who is described as white with short blond hair, possibly fair, and about 6ft tall with a slim build.
The German national is known to have been in and around Praia da Luz on the Algarve coast at the time Madeleine vanished on May 3, 2007, while on holiday with her parents, Kate and Gerry McCann, and her twin siblings.
A half-hour phone call was made to his Portuguese mobile phone around an hour before Madeleine is believed to have gone missing.
The suspect, who is in prison in Germany for an unrelated matter, has been linked to an early 1980s camper van - with a white upper body and yellow skirting, registered in Portugal - which was pictured in the Algarve in 2007.
Scotland Yard said he was driving the vehicle in the Praia da Luz area in the days before Madeleine's disappearance and is believed to have been living in it for days or weeks before and after May 3.
He has also been linked to a 1993 Jaguar XJR6 with a German number plate seen in Praia da Luz and surrounding areas in 2006 and 2007.
The day after Madeleine went missing, the suspect got the car re-registered in Germany under someone else's name, although it is believed the vehicle was still in Portugal.
Both vehicles have been seized by German police.
Scotland Yard is launching a joint appeal with the Federal Criminal PoliceOffice of Germany (BKA) and the Portuguese Policia Judiciaria (PJ).
Detective Chief Inspector Mark Cranwell has spoken of this "significant development" in the case and has urged people to come forward with information.