Twin toddlers — a boy and a girl aged 23 months — have been killed in a house fire in the northern B.C. community of Mackenzie.

RCMP said five family members were inside the townhouse on Kerry Crescent when the fire broke out at around 7:30 a.m. PT Tuesday. Three people, including a 3½-year-old girl, managed to escape.

When firefighters and police arrived, they found the building fully engulfed in flames.

A photo taken shortly after the twins were born shows them in infant car seats (Facebook)The parents — Lanora Baxter and Rick Fleury — along with RCMP officers, firefighters and a civilian, tried to get inside to rescue the toddlers, who were in a second-floor bedroom, but police said the fire was too aggressive.

"This is a tragic loss not only for the family but also the entire community," said RCMP Sgt. Syd Lecky in a statement. "Victim services and a critical incident team are assisting the family, first responders and the community with this devastating situation."

'It's devastating'

Helen Sutherland lives three doors down from the home where the fire occurred.

The upper floors of the house, where the two young victims slept, was heavily damaged in the fire. (CBC)"I was having coffee and I just seen smoke and all of a sudden, big flames shooting out of the kitchen and whipped through to the living room. I just seen the fire, I just ran to my neighbour's and there was nothing we could do," she said.

"We're a close-knit community and it's hit too close to home. It's devastating."

Neighbour Devon Calder grabbed her son and ran outside after she heard screams coming from a home a few doors away.

Mackenzie, B.C.

"[I] just heard the people screaming outside and I looked outside the window and all I seen was smoke," Calder said. "It was just really smoky, and the power lines, those were sparking and there was just flames pouring out of the windows."

The cause of the fire is still under investigation.

A trust fund is being set up at the Scotiabank in Mackenzie to help the surving family members, who had just recently moved into the townhouse.