UPDATE: Crews battling significant fire in Chinatown

The intersection of Spadina and Dundas has been reopened after a fire at a building in Chinatown.

There's still no word on the cause, but the building appeared to have housed a commercial unit on the lower floors, with apartments overhead.

Toronto's Fire Chief says a firefighter was injured and treated at the scene, but "is going to be fine".

There have been no other injuries reported.