Emergency services were called to Tile Hill
Up to six people were thought to have been injured when an unknown gas was sprayed at a block of flats.
All three emergency services were called to flats on Rosemary Close in Tile Hill.
Police, fire crews and ambulance were all called to initial reports of a gas leak.
However when fire crews arrived, it was revealed an unknown substance had been released and up to six people had inhaled it.
A number of resources from the emergency services were sent to the scene.
Paramedics treated several people and while the substance has not been identified, a spokesman for West Midlands Ambulance Service said it may have been CS gas.
