The chief suspect in the disappearance of Madeleine McCann could cash in by selling his story, it emerged today.

Robert Murat, 33, who denies any knowledge of the four-year-old's whereabouts, has contacted public relations expert Max Clifford at his London office asking him to represent him in any dealings with the media.

Mr Clifford confirmed that Mr Murat had contacted him, but said he would not formally represent him unless he was cleared of suspicion of kidnapping-the four-year-old girl.

He said: "When I spoke to Robert he was in tears and said: 'I am innocent and I will prove I am innocent,' and thanked me for listening to him. I told him that provided he is cleared I will be happy to talk to him."

It was revealed today that Mr Murat, 33, has collapsed in front of his family as the strain of being the only suspect begins to tell.

It was the second time he had fainted since he was questioned over the probable abduction of Madeleine from her parents' Portuguese holiday apartment in Praia da Luz on 3 May.

Tuck Price, a family friend of the Murats, said: "He collapsed right in front of his entire family."

Mr Murat believes DNA tests could prove his innocence as early as this week. But Portuguese police indicated that the suspect was still their strongest line of inquiry. A senior source said: "All hypotheses are on the table, we are working on one stronger one."

Mr Clifford added that the handling of the huge media interest following Madeleine's disappearance had been "very successful". But he warned that the huge rewards on offer for information - totalling more than £2.5 million - could "waste an awful lot of valuable (police) time".

Meanwhile British holidaymakers who stayed at the resort where Madeleine went missing are being asked to pass their holiday snaps to police.

The photos will be scanned through a computer database which can search for the faces of known paedophiles who may be in the background of a shot.

British police made the appeal yesterday to those who stayed at the Ocean Club Resort in Praia da Luz in the two weeks before the girl's disappearance on May 3.

The Child Exploitation and Online Protection Centre will search the pictures and any potential leads will be passed to the Portuguese authorities.

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The Protection Centre has designed a special software system in a bid to find Madeleine and whoever took her.

ChildBase, normally used to track down victims and offenders in internet child pornography images, has now been enhanced so that it can be used to search the holiday snaps.

Jim Gamble, chief executive of CEOP, asked holidaymakers only to send pictures that include strangers.

He said: "Many people both here and abroad have already helped in a number of ways in assisting the hunt for Madeleine. But now we need to go further and by asking for photographs taken in the area we can utilise the latest technology to build a larger intelligence picture.

"The CEOP centre has already applied facial recognition software in our wider work and now by taking pictures from the public we can move the investigation forward - looking for people who might seem out of place or behaving strangely.

"No matter how small or insignificant the information may seem to you, it could be the missing part of the jigsaw so let us decide if it is important.

"We are looking for anyone who was at the Ocean Club Resort or surrounding area in the two weeks leading up to Madeleine's disappearance on Thursday 3 May who have photographs that might help our work.

"We don't want scenery shots or pictures that just show your family but look at your prints and see if there are, for instance, people in the background of the picture that at first you may not have noticed."

Tuck Price said the appeal for holiday photographs showed that Portuguese police knew they had the wrong suspect.

He added: "Why else would they be doing this? If they are so convinced about Robert, why would they still be looking?"

It is understood Portuguese police have already been going through all the photographs taken by the McCanns and their friends before Madeleine was kidnapped from her family's holiday apartment.