The emergency services in Derbyshire are currently dealing with an incident at a leisure centre on Moor Lane in Allenton.
A potential chemical leak prompted the call to the Derbyshire Fire & Rescue Service at 13:38 hours, and firefighters from multiple stations are in attendance.
They are supported by a specialist Environmental Protection Unit and are working closely with colleagues from Derbyshire Constabulary and East Midlands Ambulance Service.
The leisure centre is being evacuated as a precaution while emergency services deal with the incident.
At present, around 12 people have been experiencing breathing difficulties and are being assessed by paramedics at the scene.
Osmaston Park Road is currently closed to the junction with Moor Lane, and residents are advised to avoid the area and find alternative routes.
The situation is being closely monitored, and a further update will be provided at a later time.
The authorities have apologized for any inconvenience caused by the incident.