A close friend of Madeleine McCann’s parents said yesterday that a “hurtful and ludicrous” smear campaign was being conducted against the family.

Rachael Oldfield, who was dining with Gerry and Kate McCann when Madeleine disappeared, was responding to reports in Portuguese newspapers claiming that police believed Madeleine had been killed and her family and friends had information about her death.

Diario de Noticias claimed that intercepted e-mails and telephone conversations between the friends had influenced the police’s new theory that Madeleine had died in their apartment in Praia da Luz on May 3 rather than being abducted.

Mrs Oldfield, 36, said yesterday that she thought Portuguese police were briefing against the family. “I think there are some leaks coming from the police because a lot of what I have read is completely untrue,” she said. “It is very hurtful and it is all rather ludicrous. But it is difficult to defend ourselves because the investigation and everything in it is confidential.”

Mr and Mrs McCann are due to be reinterviewed separately at the headquarters of the PolÍcia Judiciária in Portimão as part of a review of the investigation led by British officers. A sample of what is thought to be blood, taken from the apartment in the Algarve, was due to arrive in Britain for analysis yesterday.

Mrs Oldfield’s comments follow a claim by the husband of a woman serving 16 years in jail in another missing child case in the Algarve that Mrs McCann was being set up by Portuguese police to take the blame for Madeleine’s death.

Leandro Silva, who claimed that the conviction three years ago of his wife, Leonor Cipriano, for the murder of her daughter Joana had been a miscarriage of justice, said: “Joana’s mother never did anything and she was arrested. I am fearful the same thing will happen to Kate McCann.”

Goncalo Amaral, one of the officers co-ordinating the inquiry into Madeleine’s disappearance, was charged in June along with four other officers with offences relating to the inquiry into the disappearance of Joana, who was 9. It is alleged that Mrs Cipriano was beaten into a confession.

In another development yesterday, Belgian authorities said that a DNA sample taken from a drink bottle in a restaurant where Madeleine McCann was reported to have been spotted last month was that of a man. The country’s police said, however, that the tests did not categorically prove that Madeleine had not been present.

Belgian police had removed a bottle of yoghurt and a fruit juice drink from a restaurant in the Flemish town of Tongeren, where a witness said that she had seen a girl resembling Madeleine with a Dutchman and an English-speaking woman on July 28. Katja Vandoren, a spokeswoman for Belgian prosecutors, said that the DNA profile had not matched any of the profiles held on Belgian and Dutch databases.

In a rare solo interview yesterday, Mrs McCann refused to comment on developments in the case but said that reported sightings of her daughter, even if they turned out to be false, helped her to remain positive. Speaking to BBC Radio 4’s Woman’s Hour, Mrs McCann, 38, from Rothley, Leicestershire, said: “We haven’t had any news to the contrary that Madeleine isn’t alive, and that’s very important.

“And there have been many cases of children that have been found much later than this so again that’s reassuring. So the hope’s still there.”

Mrs McCann also said that she supported the introduction of a Europe-wide “quick response” system to reports of child abductions, saying that she had been “horrified” to learn the scale of the problem. She said that the sex offenders register and system of Criminal Records Bureau checks should be enforced across Europe, adding that the United States seemed to be far ahead in its ability to respond to child kidnappings.

The police team conducting the case review, including two British officers, are searching coves along the Algarve coast using information provided to them by an oceanographer at the University of Algarve.

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