By Paul Bentley and Rebecca Camber and Gerard Couzens and Mark Duell Scotland Yard detectives flew in to Portugal last night ahead of excavation at the holiday resort where Madeleine McCann vanished. But the arrival of the team, led by Detective Chief Inspector Andy Redwood, comes as tensions with the Portuguese authorities escalated, with fears the investigation could be derailed at any point. After almost two years of delicate negotiations, Scotland Yard has been given permission to start digging at sites surrounding the holiday resort in Praia da Luz where the youngster disappeared seven years ago. Scroll down for video
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Portuguese authorities approved Scotland Yard's plans to excavate site
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But they blocked request to search homes of suspects at Algarve resort
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Suspects were working at Ocean Club resort when Madeleine vanished
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They 'carried out break-ins at resort in run-up to Maddie's disappearance'
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But investigators are starting to dig waste ground at Praia da Luz resort
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Despite huge interest in case, Portuguese police are demanding secrecy
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They have threatened to halt their search if media is given information
A large wasteland yards from the @placeholder complex will be dug up,