Kate McCann, the mother of missing Madeleine, said she wants to "stop the damage" she believes is being caused to the search for her daughter by a former police chief's book.
Mrs McCann is in Portugal where she attended the first hearing of the family's libel action against Goncalo Amaral - the former detective who made allegations about Madeleine's disappearance.
Mr Amaral's accusations are strongly denied by the McCanns who claim his book has damaged the hunt for their missing daughter and exacerbated the anguish suffered by her relatives.
Speaking to the press, Mrs McCann said: "I'm here today for Madeleine and obviously I strongly hope for justice.
"I'm here to stop the damage that has been caused and is still being caused, both directly and indirectly, to the search for our daughter."
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