CALGARY – An early morning house fire in a northwest neighbourhood left one home with extensive damage and sent its occupants into the frigid conditions.

Fire crews responded to a home on Citadel Heights N.W., in the community of Citadel, at approximately 2 a.m. following reports of a fire. Firefighters encountered significant smoke and flames pouring from the front of a two-storey home and additional resources were deployed to the scene.

The occupants of the home, seven people and a pet, had exited the burning building prior to the arrival of emergency crews.

The fire was extinguished following what CFD officials called an "aggressive offensive attack," but the home was significantly damaged. Two vehicles that had been parked in the attached garage are considered unsalvageable. The siding of a neighbouring home was melted by the heat.

No injuries have been reported.

Crews remained on scene for several hours to ensure hotspots did not reignite. An investigation into the cause of the fire is underway.