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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Mixture of sunny spells and scattered showers today.
Shoppers at a Tesco store in Boston in Lincolnshire have reported that the building has been evacuated because of flooding.
Your evening weather forecast with James Wright.