Madeleine McCann disappearance: Portuguese police find 'relevant clue' in dig

Portuguese authorities found materials that could be relevant clues to the location of Madeleine McCann during their search this week of the Arade reservoir 31 miles from where she went missing.

As the police wrapped up the search on Friday, they said that they had found "some material that will be subjected to the competent expertise," according to Sky News.

Police added that they would hand over the materials to German authorities.

The Portuguese authorities did not specify what kind of materials they found, but German prosecutor Christian Wolters told Sky News that "any discovery of clothing could help the investigation."

Whether or not this material helps investigators find McCann, the results can take months to come back from the labs.

Why did police decide to do the dig?

The search in the reservoir was began this week and went on for three days after a request from German and British investigators to Portuguese police following a tip that Christian Brueckner frequented the site and visited it a few days after McCann's disappearance in 2007.

Brueckner was named a person of interest last year and is currently serving a prison sentence for raping a 72-year-old woman.

The then-three-year-old Madeleine disappeared in Portugal in May of 2007 while on holiday with her family. Her parents put the children to bed and then went out to dinner with friends in the resort, going back to check on the kids every half an hour, but one of the times a parent went to check in, they found McCann's bed empty, and she was never found.

The disappearance came back into the spotlight a few months ago when a woman going by both Julia Wendel and Julia Faustyna opened an Instagram account dedicated to her claiming that she believed she was McCann.

The announcement resulted in DNA tests in the US that definitively concluded that she was wrong.