An international search is under way to identify the parents of a blonde girl found in the care of a couple on a Roma camp in Greece.
DNA tests have shown the four-year-old is not related to the pair - and their accounts of how she came to be living with them differ.
Police found the girl, who recognises the name Maria, during a raid on the camp, in Farsala, central Greece, on Wednesday.
She has now been taken into the care of a Greek charity called The Smile Of The Child , which has put out a Europe-wide alert.
A statement from the charity said: "The features of the girl and the controversial claims of the persons who claimed to be the parents of the child led the authorities to collect a DNA sample test.
"The results of DNA testing proved that these people are not the biological parents of the child.
"The Smile of the Child in co-operation with national police authorities is taking all necessary steps to inform the competent actors at national and international level."
The director of The Smile Of The Child praised an observant prosecutor who went on the camp raid along with dozens of police.
Costas Giannopoulos told Greece's Skai TV: "She saw a little blonde head poking out from under the bedclothes. It struck her as odd, and that's how it all started."
Vassilis Halatsis, the police chief handling the case, told Sky News that despite a flood of local and international calls to domestic media and social groups, no parent has come forward to claim the child.
"That makes the case so much more difficult for us," he said.
He said authorities will release pictures of the arrested gypsy couple on Monday and hope it will unravel the mystery surrounding Maria.
Another reason detectives suspect the case could be part of an international trafficking ring is that Greek police records show a related kidnapping case in 2009, the year Maria was born.
Apparently, the couple's various excuses included that the girl was found in a blanket and that she was handed to them by strangers. They later claimed she had a foreign father.
Maria is described as: born around 2009, white, with blue eyes, long blonde hair, 100cm tall and weighing 17kg.
The couple - a 39-year-old man and a 40-year-old woman - have been arrested and are now under investigation for abduction and falsifying identity and family certificates.
They claimed to have 14 children, police said, and had registered different numbers with authorities in three different parts of Greece. Including Maria, the couple only actually had four.
The woman is also said to have claimed to have given birth to six children within a space of less than 10 months.
Police say they also found drugs and unregistered firearms in other parts of the camp, which is about 170 miles (280km) north of Athens.
Officers are now working on the theory that, because of her appearance, Maria may be northern or eastern European.
Her discovery has given hope to the family of Ben Needham - one of the longest-running missing persons cases in British history.
The boy disappeared from outside his grandparent's farmhouse on the Greek island of Kos in 1991.
Ben's sister Leighanna told Sky News: "I believe that the camp the little girl was found in was looked at (during the investigation into her brother's disappearance).
"But 22 years ago, the Greek police were scared of the gypsies and pretty much point-blank refused to go into the camps...so our inquiries into these camps never fully got covered."
The case, which some people have likened to the Madeleine McCann disappearance, has raised concerns about how easy it appeared to be for people to get official documents for children who are not their own.
A spokesman for Madeleine's family said: "This gives Kate and Gerry great hope that Madeleine could be found alive."
A lawyer for the Roma couple, Marietta Palavra, claimed on Saturday night that Maria's mother had given the youngster up at birth.
She said: "We're talking about a woman who could not raise this child and who gave it to the couple in 2009 through a third party shortly after her birth."
Her colleague Konstantinos Katsavos, who also represents the couple, added: "There has been no kidnapping, no robbery, no trafficking. They did not buy the child."