Two people have been taken to Christchurch Hospital in a moderate condition following an evacutation of the University of Canterbury's biology department.
Fire and Emergency said it was called to the university's Ilam campus at 6.30pm this evening after reports of a chemical smell.
The building was evacuated and St John assessed two people.
Five fire engines are still at the scene, as well as a hazardous material unit.
Fire and Emergency said it does not know whether chemicals were spilled or not.