British police are hoping to interview a convicted paedophile in Germany who is being investigated over the disappearance of Madeleine McCann.

Raymond Hewlett, 64, is alleged to have been staying near the McCanns' holiday flat in Praia da Luz, Portugal, when the little girl went missing in May 2007.

UK-born Hewlett, a former soldier who previously lived in Blackpool and Telford, was jailed several times for sexually assaulting young girls.

He is now reportedly being treated for throat cancer in hospital in the German city of Aachen, but is wanted for questioning by British detectives.

West Yorkshire Police have confirmed they are seeking him in connection with an indecent assault in 1975.

"We have made contact with the German authorities. We are just waiting for clearance so we can actually go and speak to him regarding that incident," a spokeswoman said.

"We cannot go into details on the incident."

Two retired UK detectives hired by Madeleine's parents to search for their daughter hope to interview Hewlett with the help of British police.

A source said: "A proper police force such as West Yorkshire may get first crack. It's then a question of us liaising with the police to see what access we can get."

But the source added: "He is one of a number of possible leads that we are looking at. We are not going to give it any more weight than that. We are being quite cautious on this."

Questions have been raised about Hewlett's time in Portugal by a couple who met him on holiday, according to newspaper reports.

Alan and Cindy Thompson said the sex offender was living with his wife and six children in a converted Dodge truck travelling from campsite to campsite in the Algarve and southern Spain.

Hewlett allegedly told the couple he was approached by some "Gipsy tourists" offering to buy his daughter just before Madeleine went missing.

They also recalled him mentioning a "business" trip to Morocco, where there were several alleged sightings of the little girl in the months after her disappearance.

Meanwhile, Goncalo Amaral, the disgraced former Portuguese police chief who led the inquiry into Madeleine McCann's disappearance was convicted of perjury in a separate case and given an 18-month suspended sentence by a court in Portugal.

Clarence Mitchell, spokesman for Madeleine's parents Kate and Gerry McCann, said the couple thought the conviction "speaks for itself" and would be continuing their defamation action against Amaral.

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