FRIENDS of Gerry and Kate McCann face renewed interrogation by Portuguese police, it emerged last night.

Reports claimed more Brits could be named as suspects by cops investigating the disappearance of Madeleine.

According to Portuguese newspapers, detectives have now come up with the unlikely theory that the McCanns had help disposing of Maddie’s body and covering their tracks.

Correio da Manha claimed: “The Judicial Police believe Kate and Gerry could have had the help of a third person in hiding Madeleine’s body.

“Or at least, that some of the friends who were with them on holiday in Praia da Luz could have helped them to cover up the lie.”

Police sources yesterday said tests were being carried out on blood found in the apartment next to the McCanns’. Investigators believe it could hold the key to where Maddie’s body might have been stored.

The holidaymakers staying in the apartment at the time were not identified, and it was unclear whether they were with the McCann group.

Details of the blood samples were disclosed amid claims this week that Maddie died from an overdose of sedatives. Sources said police were working on the theory that she was drugged.

Gerry and Kate have repeatedly denied any involvement in Maddie’s disappearance and have insisted there is no evidence against them.

Dr Russell O’Brien, 36, one of a nine-strong party on hols with the McCanns when Maddie vanished, is among those who face new questioning.

He was first quizzed after police discovered he lives in Exeter, Devon — where original suspect Robert Murat visited his sister Samantha ten days before Maddie vanished in May.

Dr O’Brien’s partner Jane Tanner, 36, is also a crucial witness and is likely to be interviewed again.

She told police she saw a man carrying a child wrapped in a blanket away from the Ocean Club apartments in Praia da Luz shortly before Kate found Madeleine had gone.

Her statement supported the theory that Maddie was abducted. But police sources said her sighting had now been discounted and the man she saw was NOT carrying a child.

Other McCann friends Fiona Payne and Rachael Oldfield told police they saw Murat at 11.45pm, wrecking his alibi that he was at home all night.

They may also be called back for more questioning as police try to unravel alleged inconsistencies.

Doctors Kate and Gerry, both 39, who were dining at a nearby tapas bar when Madeleine was abducted, have always totally rejected any suggestion that their friends could be involved.

But Correio da Manha claimed: “There are details in the friends’ statements which do not add up.

“The friends contradict each other and themselves in their statements, in their timetables and who was the last person to see Madeleine.”

The friends — who all deny any involvement — may be asked to return to Portugal next week. Alternatively, Portuguese police could travel here to sit in on interviews with British cops.

But sources said moves to make the friends official suspects, or “arguidos,” would be difficult without more information.

Investigating judge Pedro dos Anjos Frias has been asked by prosecutors to authorise new searches in the hunt for clues.

Surveillance is continuing along the coast, and police with sniffer dogs will re-examine caves and search for places where earth has been moved. The McCanns, of Rothley, Leics, have faced a wave of allegations in Portugal’s press, supplied by police sources who are banned by law from discussing the case.

Sources said Kate — named a suspect after an 11-hour grilling — will be asked back to Portugal to be questioned in days.

She and Gerry, also a suspect, insist Maddie is still alive and this week challenged police to prove otherwise.

Lawyers have advised that Portuguese authorities will struggle to mount a prosecution if the child is never found, and forensic evidence from the McCanns’ hire car is said to be insufficient for a case.

A high-ranking police source last night admitted officers had “nothing concrete” — and said that even if DNA evidence matched Maddie 100 per cent “it would prove nothing”.

The McCanns say cops bungled the inquiry and are now trying to make them scapegoats.