There were no details on how many people died or how many had been on board but the premier of the Northwest Territories put out a statement mourning those lost in the crash.

"It is with a heavy heart that I express my deepest condolences to the families, friends, and loved ones of those who were aboard the Northwestern Air flight that crashed outside of Fort Smith today," Premier R.J. Simpson said.

Chief coroner of Northwest Territories Garth Eggenberger confirmed there were fatalities but said officials would not be providing any further information until next of kin are notified.

The Royal Canadian Mounted Police did not immediately respond to requests for comment.

The Fort Smith Health Centre said it activated its mass casualty protocol at approximately 8:50 a.m. in response to "an aviation incident near the community," to free up resources to respond.

A team of investigators has been deployed to look into the accident involving a BAE Jetstream aircraft, TSB said, adding that it was gathering information.

(Reporting by Utkarsh Shetti in Bengaluru and Nia Williams in British Columbia; Editing by Sandra Maler)