We would urge anyone with information to come forward. Such behaviour is totally unacceptable and will not be tolerated. Our staff have a right to go about their jobs without facing fear, intimidation or abuse of any kind.
Anyone with information is asked to contact to British Transport Police on 0800 40 50 40 quoting background reference B7/LNA of 16/04/2013. Information can also be passed to the independent charity Crimestoppers, anonymously, on 0800 555 111.
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Sunday's weather for the east with Philippa
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More than 300,000 people have now signed a petition calling for tougher penalties for those who abuse animals.