A teacher has been rushed to hospital and nine children have been treated at the scene after receiving electric shocks at Briercliffe Primary School.
The North West Ambulance Service was called out to the school just after 1pm, with three ambulances, two operational managers, a rapid response vehicle and a number of patient transport vehicles to help.
One teacher was taken to the Royal Blackburn Hospital, with burns to the hand, and nine children were being treated at scene.
None of the casualties are considered to have life-threatening injuries.