Police revealed CCTV had been 'crucial' in the hunt for missing schoolgirl Alice Gross CCTV has played a 'crucial' role in the hunt for missing schoolgirl Alice Gross who disappeared more than four weeks ago. Scotland Yard said it had scoured footage from hundreds of cameras in a bid to trace the 14-year-old who was last seen crossing a towpath at Grand Union Canal in west London on August 28. Officers are reviewing film from around 300 cameras over a six-mile square area as the search for Alice enters its fifth week. But while CCTV has aided investigations, police said they were also relying on the public to turf up new information.
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Scotland Yard said footage from around 300 cameras was being reviewed
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Search for missing schoolgirl last seen on August 28 entering its fifth week
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Alice was last captured on CCTV crossing a towpath at Grand Union Canal
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The search is the largest use of police resources since the 7/7 bombings
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Fifteen minutes later murderer Arnis Zalkalns cycled over the same bridge
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Forensics team scoured Elthorne Park in Hanwell, west London, yesterday
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No new evidence was found at the park near to where Alice was last seen
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A reconstruction of Alice's last known movements was staged and televised
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More than 150 people contacted police following its airing with information
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Her family made emotional appeal to schoolgirl to return home on Thursday
Officers are still searching the @placeholder, where a six-inch knife was discovered last week.