Madeleine McCann Disappearance Under New Investigation in Portugal

In the newly reopened investigation into the disappearance of Madeleine McCann, a British toddler who went missing while on vacation with her family in Portugal in 2007, Portuguese police have agreed to team up with Scotland Yard.

McCann was just days away from her fourth birthday when she disappeared from the family's rented vacation apartment in Praia da Luz, Portugal, in May 2007. Her parents had been out to dinner with friends, leaving McCann and her twin siblings asleep in the residence unsupervised.

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The Portuguese police's handling of the case — which saw parents Kate and Gerry named as suspects before eventually being cleared — and their decision to shelve the investigation in 2008 has been widely condemned by the British newspapers and tabloid media.

Earlier this summer, Britain's Home Office decided to fund a new, full-scale investigation into McCann's disappearance. Scotland Yard has always maintained that the girl might still be alive, having found no evidence to the contrary.

It wasn’t clear at first if Portuguese authorities would cooperate with the new investigation, which would have been difficult because the case falls under their jurisdiction. But British officials said this week that the two forces are now united.

"We have visited Portugal on 16 occasions," Detective Chief Inspector Andy Redwood told ABC News. "The Portuguese have worked with us. We are working carefully and closely together now in order to progress this case."

Scotland Yard has already compiled a list of 38 "persons of interest." Twelve are British nationals believed to have been in Portugal at the time of McCann's disappearance.

Police also plan on questioning Antonio Castela, a 73-year-old cab driver who said he remembers possibly picking up McCann and at least two men and one woman the night of the abduction.

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