A man, 48, is dead after a house fire in Regina's northwest early Friday morning.

The fire was reported in a duplex at 378 Markwell Dr. at 1:15 a.m. CST.

When Regina fire department crews arrived, there were flames coming out of the roof. Crew found the main floor and basement on fire.

The man was found inside, close to the door. Firefighters carried him outside and paramedics worked on him, but he died at the scene.

Deputy Chief Layne Jackson said it's believed the victim was the only person staying on that side of the duplex, but that has not been confirmed yet.

"Given the extensive damage, we've been unable to complete a thorough search yet. That's yet to come with the investigation process," Jackson said.

Investigators from the fire department, city police and the coroner's officer are involved in the case now, he added.

On the other half of the duplex, which was protected by a firewall, there were two other people who got out safely.

"We had to wake those people and get them out; we had to force entry into there and get them out", Jackson said. They were not injured.

Fatal duplex fire Regina 374 Markwell Drive

A Regina fire department spokesman said the fire was intense, and involved the basement, main floor and the roof when they arrived. (Peter Mills/CBC)

Firefighters fought the blaze for 3½ hours. 

By 6:30 a.m. CST, firefighters had left, but police remained on the scene.

CBC News was told it's being treated as a crime scene. 

Fire officials initially said one person was taken to hospital with critical injuries. Later, the department confirmed that the man died.

There's no estimate of the damage, but it's believed to be extensive.

After fighting the blaze for about 20 minutes, firefighters were forced to go into a defensive mode, just trying to protect nearby buildings.

The name of the victim hasn't been released.