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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A Nottinghamshire Police officer has been nominated for a Bravery Award for helping a man who was threatening to jump off a bridge.
James Golding, who has survived cancer twice, has broken the record for the furthest distance cycled in seven days.
The Crown Prosecution Service is to announce its decision later on whether individuals and organisations will face criminal charges.