One man remains in hospital in critical condition after he was rescued by off duty first responders from an overnight fire in a St. Catharines apartment building.

Firefighters say the blaze started around 11:30 p.m. Wednesday on the second floor unit above one of the cafes on St. Paul Street near James Street.

Crews arrived to find flames raging, with smoke pouring from the building’s roof.

Following hours of battling the fire to keep it from spreading, crews were finally able to get it under control a couple hours later.

One man who was inside the affected building at the time is now being treated at Toronto’s Sunnybrook hospital where he is reportedly in critical condition.

Officials say he was rescued when two off duty police officers and an off duty paramedic saw the fire and ran in the building to get him out.

Those off duty officers are from the York Region and Toronto, according to Niagara police.

Mike Bird, an investigator with the Fire Marshal, says that was a lifesaving decision.

“We don’t recommend going into a fire. Leave that to trained firefighters with the proper equipment. But they certainly acted as great citizens at this time of the year and certainly saved his life.”

People in neighbouring buildings say they were scrambling for safety after being woken up by firefighters.

There was, “banging on each and every door from our apartment telling us to evacuate from the fire.” said one neighbour.

“I was sleeping and I was woken up by him telling me we gotta get out, the building is on fire.” said another.

Investigators were left to go through the remains of the scorned building into the day Thursday as they try to determine the cause of the fire.

“We’re early in the stages of investigation. We have extensive damage on the second floor apartment. Right now what we’re going to be doing is trying to determine the area of origin first.” said Bird.