Updated

Police in Britain have released images of a man whose identification is of "vital importance" to the investigation into the 2007 disappearance of a 3-year-old girl from a Portuguese town.

The two so-called "e-fit" images, constructed digitally with the help of statements from witnesses who say they saw the man on the night that Madeleine McCann went missing will be featured in a BBC documentary on the case that will be broadcast across Britain Monday night.

The man is described as being white, aged between 20-40 years old, with short brown hair, of medium build, medium height and clean shaven.

Detective Chief Inspector Andy Redwood, the senior investigator in the case, said that while the police were pursuing other lines of inquiry in the case, "tracing and speaking to him is of vital importance to us.

"We have witnesses placing him in the resort area around the time of Madeleine's disappearance," Redwood continued.

"This is far from our only line of inquiry and there will be e-fits released of other sightings as well, who we are equally keen to trace. These people were seen on the day of Madeleine's disappearance and the days leading up to it."

In recent weeks, police have said that their investigations have enabled them to obtain a greater understanding of the timeline of events leading up to Madeleine's disappearance from the town of Praia da Luz on the evening of May 3, 2007. The girl vanished from her parents' holiday flat while her mother and father dined with friends at a local restaurant. Portuguese police dropped their investigation in 2008, but Scotland Yard opened a review of the case in May 2011.

The BBC program will also be broadcast in the Netherlands and Germany, since Praia da Luz is a popular vacation destination in those countries. According to Sky News, Scotland Yard detectives have interviewed 442 people and identified 41 persons of interest.

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