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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Friends and family of a little girl with cancer have been holding a fun day to raise funds to help her.
Fire crews say a large fire at the Zion Christian Centre in Halesowen was not started deliberately.
West Midlands weather: It will remain cloudy and wet overnight, with some heavier bursts of rain likely at times.