Four children and a teacher have been rushed to hospital after they were overcome by fumes from chemicals used in the swimming pool at their school in Wokingham.
Ambulance staff, firefighters and police were called to the All Saints Primary School after 10am when a number of children felt ill.
It is thought that fumes from the chlorine plant at the schools swimming pool leaked and were inhaled by students and teachers.
None of those taken to hospital are thought to be in a life-threatening condition.
A spokesperson from the South Central Ambulance Service confirmed that they had been taken to the Royal Berkshire Hospital.
They added, "Ambulance staff including a rapid response vehicle and an emergency care doctor examined numerous children at the scene but they did not need hospital treatment."