McCanns in six-month wait to find out why they are suspects in the case of missing Madeleine

Portuguese police files setting out the alleged evidence against them were due to be made public on January 3, but are now expected to be kept secret until as late as July, sources revealed yesterday.

Under Portuguese law, secrecy restrictions on police files would be lifted after eight months to allow the suspects' lawyers to see the evidence against them.

But detectives have not completed their investigation and want to re-interview the McCanns and their friends.

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The public prosecutor is expected to be granted an extension to accommodate this, meaning evidence remaining secret for up to six months.

The McCanns, both aged 39, now fear their lawyers could face a protracted legal battle to get their official suspect, or "arguido", status lifted and might even have to take the case to the European Court of Human Rights.

Under Portuguese law there is no deadline which forces police to charge someone or lift their suspect status and there have been cases of people remaining arguidos for more than seven years.

The couple, of Rothley, Leicestershire, are desperate to have their arguido status lifted so they can talk freely about the case.

Their spokesman Clarence Mitchell said: "Kate and Gerry feel it is a huge distraction and while police are looking at them they are not searching for Madeleine. The suggestion they were involved remains very upsetting to them."

Portuguese police have prepared letters of appeal setting out more than 100 questions they want the socalled Tapas Nine to answer about the night Madeleine disappeared from Praia da Luz in May. Magistrate and legal expert Carlos Casimiro said police would be 'desperate' to extend the secrecy deadlines.

He told the Portuguese newspaper Diario de Noticias he thought the most likely outcome would be "the delay of the investigation in a desperate attempt to seek enough evidence to make an accusation".

He added: "This is an exceptionally high-profile case and it is the country's image which is at stake."

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Meanwhile, the police investigation hit another dead end yesterday when it emerged detectives had traced and eliminated all British paedophiles known to have links to the Algarve.

British police gave their Portuguese counterparts a list of 52 known or suspected child sex offenders who they believed could have been in the region at the time Madeleine vanished.

Mr Mitchell said: "If reports are correct, then we are pleased that police are doing their jobs properly.

"But there are also people who aren't on any lists who need to be traced."

One man who may not be on any list as he has never been convicted of an offence in Britain is part-time barman and disc jockey Christian Ridout.

The Daily Mail told yesterday how the 32-year-old fled Praia da Luz after being accused of grooming a 12-yearold girl for sex. When he vanished two years ago he was working at an expats' pub 200 yards from where Madeleine disappeared.