Greenfields School and Sports College in Goldings, Northampton has been evacuated following a suspected chemical leak.
Police are still at the scene to deal with traffic management and support the Fire and Ambulance services. No children have been hurt as a result of the incident.
Residents in the immediate area have been asked to keep windows and doors closed whilst the incident is dealt with.
Two adults are being treated at Northampton General Hospital with mild breathing difficulties.
More top news
Students from a Milton Keynes school want to turn a derelict building into a community hub - and get some work experience along the way.
Anglian Water says there will be no need for a hose pipe-ban this summer - but people need to use their supplies wisely.
MK Dons captain Dean Lewington has signed a new two-year contract with the club.