Lawyers acting for the parents of Madeleine McCann have begun trawling through the Portuguese police files on the investigation into how their daughter disappeared, the couple's spokesman said.

Gerry and Kate McCann's legal team received notification from the authorities in Portugal that they could begin to study some 20,000 pages filed by police in Portimao, Clarence Mitchell said.

He said: "This is an important step forward in the search for Madeleine."

Rogerio Alves, the McCanns' top lawyer in Portugal, contacted the family today to say he had received official notification that the volumes can now be examined.

He will travel from Lisbon to the Algarve next week to supervise colleagues. In effect, the team will have August to leaf through the thousands of pages of information collected by detectives since May last year.

Much of the information will already be familiar to the lawyers, including statements made by the Leicestershire couple.

But the McCanns were largely kept in the dark about the official inquiry because of Portuguese laws governing police investigations.

Mr Mitchell said: "Kate and Gerry have long wanted to know what was in the police files and what was and wasn't done in terms of the search for their daughter.

As well as potential leads, the McCanns' lawyers will be assessing whether the files would support legal action against Portuguese police for the way they conducted the inquiry.

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