The girlfriend of suspect Robert Murat has denied a claim she was spotted with Madeleine McCann two days after she vanished.

A new witness has identified Michaela Walczuch as a woman seen with the missing girl in central Portugal about 100 miles from where she disappeared on May 3.

The new witness came forward after Madeleine's parents Kate and Gerry McCann hired Spanish private detective agency Metodo 3 to help find their daughter.

But family friend Tuck Price said any suggestion Ms Walczuch was involved in the case was "ridiculous", adding: "She would deny that 100 per cent."

German-born Ms Walczuch, 32, has already told Portuguese detectives exactly where she was on the evenings before and after Madeleine's disappearance, he said.

McCann family spokesman Clarence Mitchell said private detectives hired by the parents of missing Madeleine McCann say they are a 100 per cent certain that she is still alive.

The investigators claim theories that the four-year-old was killed in her family's holiday apartment in Portugal are wrong.

Gerry and Kate McCann have been informed of the reported sighting which is being investigated by private detective Francisco Marco.

The McCanns' spokesman, Clarence Mitchell, said Mr Marco was "very confident".

"He's 100 per cent certain that she's alive and believes that they are 'very, very close' to finding the kidnapper," said Mr Mitchell.

"Naturally we are extremely encouraged by any indication by our investigators that things are going well. But there have been a number of leads that have come to nothing and Kate and Gerry remain cautious."

The McCanns, both still official suspects in her disappearance, hired agency Metodo3 in September to boost efforts to find their daughter.

Mr Marco, head of a 40-strong-team,said: "We have a six-month agreement with the McCanns.

"We have already spent a month and a half working. I will find her before that period is up."

And he is certain Mr and Mrs McCann had nothing to do with Madeleine's disappearance.

"Our staff interviewed the McCanns for ten hours - enough time for us to tell if they were trying to fool us.

"My specialists assure me they are not hiding anything. I would not risk the prestige this agency has gained over 23 years without being convinced there is a case," he said.

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