Last updated at 12:14 20 September 2007
Kate and Gerry McCann are convinced they are being bugged by British police.
They believe their mobile phone calls and emails are being monitored by detectives collecting evidence on behalf of the Portuguese investigation.
As a result they and some of their friends and supporters go to great lengths to avoid being overheard when they are discussing sensitive issues in the case of missing Madeleine, meetforing face-to-face or talking on landlines which they believe to be harder to intercept.
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Surveillance targets? Gerry and Kate McCann, pictured yesterday, are being ultra cautious about their conversations, say friends
Read more...Their suspicions were first aroused by questions they were asked by Portuguese police which were based on information that could only have come from private conversations.
During lengthy interviews when they were first made suspects, they were asked questions which implied they had conspired during mobile phone conversations to hide who was at the dinner party - and when - on the night that Madeleine disappeared.
They are also thought to have been asked why the toddler's Cuddle Cat toy was washed twice - information that could well have come from surveillance of phone calls.
Although the couple have been back home in Rothley, Leicestershire, for 12 days, they fear the practice is continuing. A source close to the family said:
"The assumption is that it is taking place. Everyone involved is very careful, particularly with their mobile phone calls and what they say.
"There was an assumption from the early days that their mobile communications were unsafe and could be listened to.
"They believed it in Portugal and they believe that is still happening now that they are back home.
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Madeleine McCann: Missing since May 3rd"Gerry will often refuse to talk on a mobile phone - he prefers to use landlines as he considers that they are safer. They feel they are being watched at all times."
The source added: "It would be entirely wrong to say that their phone conversations are in any way furtive as a result of this.
"They are entirely innocent and have nothing whatsoever to hide - but they are being understandably cautious about what they say on the phone and in emails.
"They would obviously not want to disclose the way in which they plan to conduct their defence."
Leicestershire police yesterday refused to comment on the allegation.
But a senior police source said: "It is highly likely to be happening. There would need to be high-level meetings before anything like this could be done.
"But if I were someone in Government I would have got it done anyway to make sure that we knew as much as possible, given that the case involves UK citizens."
Dr Russell O'Brien and Jane Tanner, who were both on holiday with the McCanns, have spoken to friends of their belief that their phones were tapped in Portugal.
Portuguese detectives have reportedly admitted monitoring the emails of Robert Murat, the British expat in Praia da Luz who became the first suspect in the case.
However, this is the first time that anyone involved in the case has claimed the practice is taking place in Britain. A spokesman for the McCanns refused to comment.
? Police fitted a tracking device to the McCanns' hire car, it was claimed last night, to monitor their precise movements in the days after they came under suspicion.
A gadget the size of a wallet is capable of transmitting a signal to satellites - like a Sat Nav system in reverse - enabling police to watch where the couple go.
It is claimed the device was installed in the Renault Scenic during the 48 hours the police had the car in early August to gather forensic samples. It could have been placed in the boot or attached using a magnet under the bonnet.
It explains why detectives returned the hire car to the McCanns after their tests rather than impounding it.
"The police are not fools - they did not give the car back without reason," said a Portuguese source with knowledge of the investigation.
"They wanted to see where it would go and would have used a tracking device."
? Portuguese detectives have taken a step closer to being able to search the McCann family home.
Policia Judiciaria detectives believe something inside the Leicestershire house could yield a vital clue and have sought approval from the judge in the case to ask British officers to carry out the raid.
Yesterday Judge Pedro Miguel dos Anjos Frias agreed to the request.
• Portuguese police would have needed to apply directly to the Home Office for permission to bug a UK citizen's telephone or emails.
They would have filed a Mutual Legal Assistance request, which is the only formal way for a foreign police force to obtain evidence from another country.
Providing that the request is legal under UK law - the relevant law in this case would have been the Regulation of Investigatory Powers Act - the request would then be passed to the Home Secretary for final approval.
British police would also need Home Office permission to carry out telephone and computer taps.
Between January 2005 and March last year, the Home Office approved 440,000 requests for permission to intercept personal communications.
Most of these would be seeking telephone numbers one particular phone has called. Only a very small proportion would have been for permission to listen in on a call or read an email.
Read more: http://www.dailymail.co.uk/news/article-482815/Madeleines-parents-British-police-bugging-phone-calls-emails.html#ixzz13pGJk7vR