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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Two young children are in hospital after a garden wall collapsed on top of them in Evesham this morning.
New scientific evidence shows a soldier found dead at an army barracks more than 20 years may not have killed herself.
Leicestershire and Derbyshire will both host fixtures when the Women's Cricket World Cup comes to the East Midlands next summer.