Three people are believed missing after a house fire in Castor, which is located roughly 140 kilometres east of Red Deer, Alta. 

Firefighters were called to the home on Sunday morning. When they arrived, the home was fully engulfed in flames.

“What's particular about this is that there are three people unaccounted for," said Sgt. Josée Valiquette.

"Our RCMP forensic investigation section as well as provincial fire investigators are investigating this matter."

As of Monday afternoon, RCMP and fire investigators were not able to enter the home to search for the people.

“There are still some hot spots and until it is completely​ out, our investigators will not be able to enter the residence,” Valiquette said.

RCMP confirm the three missing people are connected to the home, but would not confirm whether they are residents.

The cause of the fire is under investigation.