There has been a major power outage in Toronto's west end Thursday evening, on one of the coldest nights of the year.

The power went out at about 10 p.m., from in patches from roughly Queen Street to St. Clair Avenue and from Spadina Avenue to as far west as Jane Street.

The culprit is a flooded Toronto Hydro substation at Bloor and Dufferin.

Toronto police say they are constant contact with Hydro, but there has not been any indication when power will be restored.

Duty Inspector Frank Bergen told ctvtoronto.ca that it's "the time to be a good neighbour" and to be vigilant of the security in both your home and others around you.

He said that the public should not be afraid to call the police to use as a resource but asked that citizens be cautious not to misuse 911.

Police have brought in additional units to the affected areas. Stop lights are without power and are to be treated as four-way stops.

Families that may need emergency shelter can call Central Family intake line at 416-397-5637. Police are recommending that citizens in the affected area consider bunking with friends with power if possible.

 The TTC used buses instead of the subway between Islington and St. George stations on the Bloor-Danforth line as of 11:45 p.m. Users on the microblogging site Twitter are reporting that the TTC appears to be running normally elsewhere.

Twitter users also reported that the lights were out at Toronto landmarks such as Honest Ed's discount store at Bathurst Street and Bloor Street.

Temperatures are expected to drop to about -20 C tonight.