Police are trying to trace a group of people seen in Figges Marsh, London, before shots were fired.
Abdirashid Mohamoud, 17, died after being chased and stabbed by a group of men in Isleworth on Friday.
The find shows the extraordinary lengths criminals will go to smuggle drugs, the Prison Service says.
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Exeter score 26 unanswered points against Bath to extend their lead at the top of the Premiership table.
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