Chasity Spence and Arnold Culley helped save four children from a burning shed on Nisichawayasihk Cree Nation this weekend.

Spence said she heard children crying and screaming inside a burning storage shed Saturday afternoon and knew she had to get them out somehow.

Chasity Spence ripped the wall off a burning storage shed to save four children on Saturday. (Facebook) "I grabbed the wall and I ripped it right off. I couldn't believe that, I'm a tiny little person and that wall was boarded on there pretty good with three other two-by-fours right over it," she said.

"The flame came out and I kind of backed away. I was going to run in there and one of the little girls came running through the fire."

Arnold Culley said he saw the burning shed and ran to help.

"[Culley] went around the back and started prying from the corner," she said. "He got that open, that little boy fell out and then the other two little girls came running out and then like two seconds after we got them out, that shack fell."

Spence said the children were badly burned – one of girls had burned hair and her skin was peeling.

"She [was] wanting me to hold her, but I'm so scared to touch her and I'm trying to comfort her and tell her not to worry, she's out, an ambulance is coming," she said. "Then the other two girls that ran out from the back came running to me also wanting me to hold them, and I was too scared to touch them."

Two six-year-old girls and a five-year-old girl were sent to Winnipeg, where one is listed in serious condition. A three-year-old boy was treated at the local nursing station and released.

The Office of the Fire Commissioner is investigating the cause of the fire.

Nisichawayasihk Cree Nation (formerly Nelson House First Nation) is located about 80 kilometres west of Thompson.