The jury at Lewis Crown court heard how Lauren Bishop, Michael Clark and Edward Phillips, met up after and celebrated by buying and drinking alcohol on the seafront.
CCTV from the Londis store nearby showed Phillips and Clarke laughing and joking shortly after carrying what the court heard was a brutal, vicious and horrific attack.
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Sunday evening's weather update for the east
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A man has been taken to hospital with serious injuries after being beaten by a gang of 10 in the early hours of this morning.