Hydro crews are replacing a burned cable they believe caused an explosion on Church Street near The Esplanade that sent a manhole cover into the air.
Police say a loud explosive bang was heard around 9:30 a.m. Sunday and brown smoke started coming from an underground grate.
Earlier it was thought that a possible hydro vault fire caused the explosion, but Toronto Hydro told CP24 it was not the case and there were no outages in the area.
Hydro crews discovered the burned cable, but do not know how it happened.
No injuries have been reported.
With files from Corinne Van Dusen