A house fire in eastern Saskatchewan has claimed a fifth life. RCMP say a 30-year-old woman died of her injuries in hospital in Saskatoon Thursday night.

The blaze in Nipawin left the woman's six-year-old twins dead as well as a 21-year-old woman and a man.

No names have been released.

On Thursday RCMP and fire investigators were combing through the charred ice-covered ruins of the family home in Nipawin, about 250 km northeast of Saskatoon.

Two men were injured as they tried to get into the burning home in a vain attempt to save the family.

"They tried to enter the home to retrieve the injured, the victims of the fire," RCMP Sgt. Carole Raymond said.

"Due to the flames, they couldn't enter the home. Then the fire department arrived and started putting a lot of water on the home. They were able to get one person out. This is a terrible loss."

The men who risked their own lives were thought to be related to the victims. They are still in hospital but police expect they will be discharged Saturday.

Volunteer firefighters responded to the blaze just before midnight Wednesday and found the home completely engulfed in flames and smoke.

Relatives and neighbours looked on in horror.

Labouring in -40 C temperatures, the fire crew managed to extinguish the flames after a few hours, but not before they gutted the house.

"Members of the family were there last night and were present when this was occurring," Raymond said. "There are a lot of people who are aware and are grieving."

The names of the dead and injured were not released.

The smoke had cleared by Thursday morning, but the deaths cast a pall over the agricultural community of 5,000. The family was well-known and the twins -- a boy and a girl -- attended a local school.

Neighbours said the couple who lived in the home were married during the holidays just last year.

Capt. Michael Ramsey of the Salvation Army said people in the town were trying to help relatives deal with their loss.

"Right now the family is still gathering and getting together," he said. "There is nothing that compares to the tragedy of losing loved ones and when youngsters are lost.

"It is indescribable and it is compounded when it happens at this time of year. I encourage everyone to keep the family in their prayers at Christmas time."

RCMP said it was too soon to determine what caused the fire.

Last April, Nipawin was rocked by a massive explosion that killed two people and injured three others. It was caused when a natural gas pipe was damaged by construction equipment.