Police in Salmon Arm, B.C., say three children were asleep in a B.C. southern Interior cabin when it was destroyed by fire early Thursday morning.

A 14-year-old girl, her 10-year-old cousin and 14-year-old male cousin, all perished in the blaze, which swept through the 400-square-foot wood cabin on the shores of Shuswap Lake, north of Salmon Arm.

The parents of the elder girl were sleeping in the main house.

Fire crews were called to the property around 1:30 a.m. Thursday, but there was little they could do.

RCMP Cpl. Dan Moskaluk said one parent suffered minor injuries while trying to rescue the children, but is expected to recover.

"Her father was out there and said 'my three kids are in the bungalow,'" neighbour John Fink told CTV.

Neighbour Darlene Clough said flames from the blaze rose, "100 to 150 feet in the air."

The Vancouver-area couple staying on the property are longtime annual visitors to Eagle Bay, and were there with their daughter and nephew, both 14, and 10-year-old niece.

Their names and other details are being withheld at the request of the family.

News of the deaths has shaken Eagle Bay, a tight-knit community of year round residents and summer vacation homes.

"Everybody's really sick about it," John Spink said.

Clough said she mourned alongside the grieving parents.

"I just asked if someone was bringing comfort to the couple that had just lost their child," she said.

"They were just sitting on the steps over there at this neighborhing house -- I prayed with them."

The B.C. Coroner's Service, Fire Commissioner's Office and RCMP are now trying to officially determine the cause of the fatal fire.

Clough suggests a smoldering campfire on the property could be to blame.

"It spread so quickly that by the time the couple got there to try to rescue them they couldn't even get in," she said.

"We're just praying God will bring them peace and comfort them."

Salmon Arm is a community of around 16,000 on the shores of the Shuswap Lake.

The area, located approximately 450 kilometres northeast of Vancouver, is very popular with tourists and campers in the summer months.

With a report from CTV British Columbia's Shannon Paterson