A man is in critical condition in a Toronto hospital after he was severely injured in an early-morning apartment fire.

Investigators are looking into the cause of the blaze, which occurred in a building at Dufferin Street and Davenport Road at about 2:15 a.m. on Thursday.

Firefighters were called to the building when a passerby noticed smoke pouring out of a third-floor window.

Fire crews rescued the man as they forced their way into the smoke-filled suite and extinguished a fire in the bathroom. The blaze was contained to one suite.

Paramedics rushed the man to a hospital, where he underwent treatment for severe smoke inhalation and burns, said Toronto Fire Services Capt. David Eckerman.

Residents were forced to leave their suites as firefighters battled the blaze and then ventilated smoke-filled parts of the three-storey building.

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