CALGARY -- One person is dead after a house fire Friday night in the southwest community of Glendale.

The Calgary Fire Department said neighbours spotted the fire on Kelwood Place SW around 11 p.m.

Fire crews found heavy smoke and flames coming from the back of the single-storey home when the arrived at the scene.

Firefighters attacking the fire found a man inside, pulled him from the house, and began resuscitation efforts.

EMS rushed the man to hospital in life-threatening condition, where but he died from the injuries he sustained in the fire, the department said.

"He was a nice guy who was very private," said neighbour Hank Beeksma. "It’s difficult to imagine while you’re sleeping in bed, your neighbour has passed away right next door to you. So it’s a real loss.”

Beeksma said he first became aware of the fire when another neighbour banged on their door and told them to get out because the house next to them was on fire. They took refuge from the -15 C temperatures in a friend's home until it was safe to go back.

He said it's not something you ever expect to happen.

"You’re thinking, OK, our houses are no more than about four metres apart and you’re wondering if there will be flames and spreading," he said. "It's your own home, somewhere you normally feel very secure, and that’s threatened."

The main floor eventually collapsed and firefighters fought the rest of the fire from outside.

Fire crews and a fire investigator remained at the property throughout the night to make sure the fire did not spread.

While crews cannot rule out whether the home was equipped with smoke alarms and carbon monoxide detectors, none were found in the initial investigation.

"Working smoke detectors save lives. In our position as fire investigators, we see it every single day. (They alert) people to get out of the home and get the emergency crews on their way. It's proven," said Travis Thiessen, fire investigator with Calgary Fire Department.

The cause and origin of the fire is under investigation.