One person is dead and another is in serious condition after a fire broke out in a highrise Toronto apartment building early Wednesday morning.

Toronto Fire District Chief Stephan Powell said crews were called to 77 Huntley Street, south of Bloor Street East, for a fire on the 7th floor of the building at 1:35 a.m.

He said they encountered heavy smoke on arrival and located one male in the unit.

Paramedics said he was rushed to Sunnybrook Hospital in critical condition but later died.

Powell said crews eventually knocked down the flames and began to ventilate the building, finding that some residents fled to the roof.

Platoon Chief Armando Schiarizza said 15 fire trucks were at the scene at one point.

Residents who fled the building were sheltered in TTC buses while they knocked down the flames.

Paramedics said a second victim was taken to Sunnybrook in serious but stable condition.

It’s the third significant fire resulting in injuries to occur at the building in the past 13 years.

Fire investigators are at the scene but the fire's cause is not yet known.