York Regional Police tactical officers work at the scene of a fatal shooting in Vaughan, Ontario (Photo: AP)

A gunman shot and killed five people in a Toronto suburb before being killed by police.

Another person who was shot by the suspect is being treated in hospital and is expected to survive.

Officers responded to an active firearm in an apartment building in Vaughan, a city north of Toronto, around 7:20 p.m. Sunday.

They discovered a “dreadful scene in which countless victims lost their lives”.

An officer shot and killed the suspect, whose identity is unknown.

Police say they have no details about the motive or whether the shooter was a resident of the building.

The victims are also currently unknown.

Police station in the lobby of an apartment building after a shooting in Vaughan, Ontario, Sunday, December 18, 2022. Authorities said several people were shot dead in part of the building in Toronto's suburbs and the gunman was killed by police. (Arlyn McAdorey/The Canadian Press via AP)

Police rushed to an apartment building on Sunday evening (Image: AP)

York Regional Police tactical officers stand in the lobby of an apartment building in Vaughan, Ontario, on Sunday, December 18, 2022. According to the police, several people were killed, including the suspect, after a shooting in part of the building. (Arlyn McAdorey/The Canadian Press via AP)

Officials said they found a “terrifying scene” (Image: AP)

“Six died. One is the subject. The other five are victims,” ​​York Regional Police Chief Jim MacSween said at a news conference.

Mr MacSween has assured locals there is no further threat to the community.

He said police had previously hoped to have residents back in their units within hours.

The Ontario Special Investigations Unit involved in a death or serious injury involving police is opening an investigation.

Mass shootings are rare in Canada, and Toronto has long prided itself on being one of the safest major cities in the world.

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