Carl Williams, Headteacher at Moreton School in Wolverhampton, has described an incident in which 20 pupils were jabbed with a diabetic testing needle as "frightening".
Some of the children have been taken to hospital for hepatitis jabs as a precaution.
An 11-year-old boy has been arrested.
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Rose Humphries believes that drug laws in the UK need to be urgently reformed and that the solution is decriminalisation.
Mainly clear and cold inland tonight, sunny spells tomorrow.
Clear and dry overnight with frost and ice.