A Queen Street building was demolished Tuesday afternoon after being gutted by a three-alarm fire that broke out after midnight.

After being assessed by structural engineers, the building was deemed to be structurally unsound and crews moved in to demolish it around 4:30 p.m.

The blaze began just after 12:30 a.m. at 369 Queen St. West, near Soho Street. The building housed a Roots clothing store and other retailers, along with apartments on two upper floors.

The cause of the fire was not immediately clear, however, Platoon Chief Eric Cotter said it’s likely that the fire was not caused by the vicious storm that ripped through the city overnight.

Camera footage of the fire shows flames rising high above the building. Large plumes of smoke billowed above the building as crews doused the fire from the street below.

After an initial search, fire crews determined that there was no one inside the upper-floor apartments.

Firefighters confirmed at about 2:30 a.m. that the main fire had been extinguished. However, crews remained on scene to deal with hotspots around the building.

Officials warned earlier Tuesday that vibrations from passing traffic could cause the building to collapse.

Police have closed a section of Queen Street -- between John Street and Spadina Avenue -- to cars, pedestrians and TTC vehicles.

Witnesses in neighbouring buildings reported hearing explosions before the fire broke out.

The Ontario Fire Marshal’s office is investigating.