THIS little girl's rag doll could have been given to Madeleine McCann by those who snatched her, investigators believe.

The cuddly plaything was among evidence suggesting Maddie was held at a remote house - but Portuguese cops abandoned the line of inquiry.

Private detectives hired by the missing tot's parents Kate and Gerry found the white bungalow in an orange orchard outside Silves, Portugal, after trailing a woman seen earlier with a Maddie lookalike.

They staked the place out and spotted the doll and a child's drawing.

Portuguese police on the Maddie case were tipped off, but the McCanns camp claim they did not fully investigate.

A source close to the McCanns said yesterday: "This is one of the strongest leads there's been in the hunt for Maddie.

"There was credible evidence at the orchard that needed proper investigation by the Portuguese - that never happened."

The private investigation began after British tourist Jean Godwin, 56, contacted the Find Madeleine hotline.

She reported seeing two woman with a girl she was "100 per cent sure" was Maddie in Carvoeiro on September 7, 2008.

Mrs Godwin, of Widnes, Cheshire, said the women were holding the hands of a "gaunt" little girl, who was wearing a "black wig to disguise her fair hair".

She was struck by the large irises in the girl's eyes - a feature of Maddie in photos.

Also a woman was seen passing a child in a blanket to a man in a car on May 5, 2007 - in Silves.

Retired care worker Mrs Godwin confirmed Mr Albino was one of the women she saw from a photo.

The photo was also shown to British witnesses who saw a couple acting suspiciously near the McCanns' holiday apartment. Several identified Mrs Albino.

Teacher Jorge Vitorino Cabral Martins - who was seen meeting Mrs Albino at the orchard property several times - was also placed in Praia da Luz by several witnesses.

McCann investigators saw Mr Martins discard a "child's drawing done by someone aged four to five". They also photographed the rag doll on the front seat of his white Citroen Berlingo van.

During a surveillance operation, Mr Martins was seen shopping for clothes and shoes for a little girl.

Neither he nor his girlfriend Maria Alice dos Santos Silveira have young children or grandchildren.

McCann 'tecs visited the Silves house pretending to be buyers. They were convinced the other woman seen with the girl was inside but no one answered.

Dave Edgar, head of the inquiry team, sent a report to Portuguese cops. It lies, with more than 50 other sightings of Maddie, in a dossier filed away at a police HQ.

It was obtained by The Sun and revealed yesterday.

Cops confronted Mrs Albino, who denied being the woman Mrs Godwin saw. A police report states: "Nothing of interest was found."

Martins and Silveira denied having anything to do with Maddie's abduction.

He said the doll was given to him by his students. Mrs Silveira said the drawing had belonged to her 28-year-old daughter.

That was as far as the police took the matter. But the McCann team are still working on the lead. The child's drawing has been sent off for forensic analysis.

Kate and Gerry, both 41, of Rothley, Leics, insist they will never give up looking for their daughter.

The source added: "After Dave Edgar sent his report to the Portuguese police our investigators heard nothing more.

"It is now clear from the files that very little was done to rule these people out as suspects.

"But it was very significant information and remains an open investigation."

  A WOMAN whose possible sighting of Maddie at a store in Dunedin, New Zealand, was revealed by The Sun yesterday has been interviewed again by police.

Checkout worker Taryn Dryfhout is angry she was not asked the questions before. She said: "They wanted descriptions of the people and how they paid. I'm sure it was Maddie. She was very afraid."

The girl was snapped on store CCTV in December 2007.

a.lazzeri@the-sun.co.uk