It is not certain that traces of blood found in a car rented by Kate and Gerry McCann match that of their missing daughter Madeleine, the director of the Portuguese judicial police said as they prepared to report to prosecutors yesterday.
"None of the results of the analyses allows one to say with certainty that the blood comes from X or Y," Alipio Ribeiro said on Portuguese public television station RTP.
"Not with mathematical precision," he said, in reference to claims by some British media outlets that the results were a perfect match with Madeleine's DNA.
The blood traces were found in a car rented by Kate and Gerry McCann 25 days after their daughter, then three years old, disappeared from the family's holiday apartment in the Algarve resort of Praia da Luz on May 3.
Citing experts from the government-owned Forensic Science Services (FSS) lab in Birmingham, the Sun tabloid reported that blood found in the car was an exact DNA match to Madeleine.
Sky News television also reported that, citing unidentified sources.
Portuguese police expected to convey a report on Madeleine to prosecutors yesterday so that they could decide if her parents, named as suspects last week, should be charged over her disappearance.
"The papers are being finished and should be sent today [Monday] or tomorrow to the prosecutor handling the case," police spokesman Olegario Sousa said earlier.
The Daily Mirror tabloid reported that the police have called for Kate McCann to be charged with accidental murder, citing an anonymous source.
"The feeling is that the forensics support the theory that Madeleine died accidentally inside the apartment on the night she vanished, and she was then moved," the source said. "There has been talk of 70 percent or 80 percent matches. The FSS doesn't do that. It's either a match or its not, it's either significant or it's not. In this case, it's significant."
For the last four months the McCanns have led a high-profile international campaign to find her, focusing on suspicions that she was abducted while they and friends were eating in a tapas bar in the same complex.
Last week Portuguese police received the results of tests of blood samples from the bedroom Madeleine had been sleeping in before her disappearance from a British laboratory.
Kate and Gerry McCann, both 39-year-old doctors, were named as formal suspects on Friday after two days of intense questioning by Portuguese police.
They returned to their home in the affluent central English village of Rothley with their two-year-old twins over the weekend for the first time as a family since Madeleine's disappearance.
"They're OK, they've had a decent night's sleep. They're holding up extremely well," said Kate McCann's uncle Brian Kennedy, adding that the twins were "fine."
Police have said, however, that the family can be summoned back to Portugal at any time.
Ribeiro said "detention during the investigation is not envisaged."