An early morning fire that destroyed two Saint John businesses and displaced up to four tenants continued to smoulder into the lunch hour on Monday.
The fire at 221 Union St. started at about 2:45 a.m.
Firefighters barricaded the road and evacuated the buildings next to the structure, located at the corner of Waterloo Street.
The building, which housed two businesses — Pawn Stars, a city pawn shop, and Waterloo Beauty Salon sustained heavy fire damage and is considered a loss, said Platoon Chief Peter Saab.
The shell of the structure is still standing, but fire gutted its interior, including three upper level apartment units.
Fire investigators are trying to determine the origin and cause of the blaze that posed several challenges for firefighters, said Saab.
"We've had a partial collapse of the roof," he told CBC News late Monday morning. "There is a fair amount of fire underneath the collapsed roof, so it's hindering us to fully extinguish the fire," he said.
"Given the shape of the buildings, they're very unsafe so we're not allowing firefighters inside … We're pumping large volumes of water and foam into the building, trying to get between the collapsed roof and the rest of the structure that's still showing some fire."
As many as four people have been displaced, according to Saab. They were not at home when the fire started, and there are no injuries. The Red Cross is assisting one of the tenants with emergency lodging and supplies.
Firefighters focused their attention on stopping the fire from spreading to neighbouring buildings.
"We had a number of challenges, one being we had a number of frozen hydrants when crews first arrived, so establishing a water supply and maintaining it was an issue," said Saab.
"Once we did get a water supply established, and the fact that given the below zero temperatures, just to keep it from freezing was a major job as well."
A city transit bus was dispatched to shelter about 10 people forced from their homes, but many found temporary accommodations.
Tenants of adjacent buildings are now allowed back home, according to the Red Cross.
Police closed a section of Union Street, from Charlotte Street to Carmarthen Street, and Sydney Street, from King Square North to Peters Street.
Saint John Energy also cut power to the immediate area, after a transformer pole near the building caught fire.