Police hunting for Madeleine McCann on the island of Malta said today that they have ruled out the only photograph taken of a little girl who resembled her.

Maltese police launched a full-scale investigation after receiving five possible sightings of Madeleine since last Saturday.

However, they have been unable to find any evidence that Madeleine has been on the island in the 50 days since she was abducted from a Portuguese holiday apartment.

A police source said: “The only report supported by evidence was made by a person who said saw Madeleine in Zejtun [in the south of Malta]. The person had enough sense to get a mobile snap shot of the girl, which resulted not being the young Maddie.”

Superintendent Pierre Calleja of the Maltese CID said that police had received the first report on Saturday of a girl who resembled four-year-old Madeleine on the Mediterranean island.

“Subsequent to this report, a full scale police investigation and a magisterial inquiry were initiated,” he said. “These investigations are actively in progress and all possible avenues are being pursued.”

The investigation, which is being carried out in co-ordination with Interpol, is centring on the tourist areas of St George’s Bay and Rivera Martinique. Identity checks have been stepped up at Malta International Airport and at the island’s ports and marinas.

Ray Roberts, 49, from Anglesey, north Wales, said that on Sunday night he saw a girl in Sliema, on the northeast coast of Malta, wearing what he said was a jet black wig as she was taken away by an Arabic looking man in his 40s and a younger woman. The man spoke to the child haltingly in English.

“It was obviously not his first language so it seemed odd that he had to speak to her in English,” he said. “As a father, their reaction did not seem natural.”

He added: “Then I noticed the little girl’s hair. It was pitch black, very thick and cut in an unusual style for a child that age - very much like a wig rather than real hair. The more I think about what I saw the more convinced I become that it may well have been Maddie.

A spokeswoman for Madeleine’s parents Gerry and Kate McCann, said that the couple, from Rothley, Leicestershire, were not giving credence to the claims at this stage.

“Their whole attitude from day one has been that they know there are going to be lots of bits of information but if they expended energy on every single one of them what would they be like by now,” she said.

“Until they hear that something has been checked out and there is a resolution of the piece of information one way or the other and that comes from an official source they are not going to focus on it.”

Mr McCann, a consultant cardiologist, today vowed to continue the search for his daughter.

“We are trying to stay focused and looking forward, and very much putting our energies into helping the search for Madeleine. That does help us to cope,” he said.

“There is a huge amount of information there, and the message we are sending out - the overriding message - is clearly ’Madeleine is still missing’. And as long as she is missing we will continue searching for her.”

Madeleine was abducted from her bed while her parents dined at a nearby restaurant in Praia da Luz on the Algarve. Since her disappearance there have been reports of possible sightings across Europe and as far away as north Africa but it is the first time that claims have been made public of a possible Maltese connection.

The McCanns will today lead a balloon release in up to 50 countries to raise awareness of the international campaign to find their daughter.

They couple will release 50 yellow helium-filled balloons on the beach at Praia da Luz. Numerous similar events have been organised across the UK and abroad, including Ireland, Argentina, the United States, Singapore, Australia - and even Afghanistan, where people will race kites emblazoned with pictures of Madeleine.

A message from the couple on the FindMadeleine website - visited by tens of millions of people - said: “The objective is simple - after seven weeks missing, we must continue to ensure she is not forgotten.”

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