Residents describe meeting a wall of smoke and flames as they scrambled out windows or down pitch-black hallways to escape an apartment fire in Burnaby, B.C.

An eight-year-old boy is among four people seriously hurt while trying to get out of the building.

The fire apparently started in the lobby of the three-story apartment building around midnight on Monday.

Bob Nath's parents and 19-year-old brother live in the building and he came to the scene after finding out about the fire.

Nath said his brother and father made it out, but lost their mother in the confusion and then his brother saw a little boy at a window.

"My brother ran back in and he was looking around. He didn't find the kid anywhere, didn't find my mother. (He) got out and fortunately my mother was lying on the lawn there ... they were trying to resuscitate her and they achieved that."

Both his brother and the boy have serious burns, and two other people also have serious injuries.

Nath said his brother came out of the building burned black.

"I mean it just tells me how ... intense the fire was in there."

Nath wept as he talked about what it would have been like for his mother in the smoke-filled building.

"She doesn't know that her sons are sitting out here waiting, both her boys," he said. "If she passes away now I won't get to see her and she won't get to see me."

By the time fire crews arrived at the scene residents were already leaping out windows.

Several suites were seriously damaged before crews managed to contain the fire, which is considered suspicious. Some building residents claim it likely started in piles of junk, including a couch and a Christmas tree, left in the building lobby.

Five other residents suffered minor injuries.

With files from The Canadian Press