The boy was electrocuted and went into cardia arrest. The ambulance service said: "He is in a potentially life-threatening condition. The quick response from school staff and paramedics gave him the best chance of survival".
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British Airways said it was taking the matter "extremely seriously" and is assisting police with their enquiries.
Firefighters in Abingdon have carried out a rather unusual rescue after a 17 year-old bellringer became tangled in bell ropes.
Saturday's weather for the west