Inspector Michael Edwards from the British Transport Police says cable theft is "an attractive proposition for would-be thieves", but that the police are cracking down on it.
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The world record attempt will raise money for the foundation set up in memory of the Olympic gold medallist, who died in May 2013.
In today's Newsweek, Carl talks about what the 'No' vote in the Scottish Referendum could mean for Wales and the impact of legal highs.
England manager talent spotting at Swansea City v Southampton at the Liberty Stadium