Photo: CTV News

Fire officials say three people are dead after a fire in a shed outside a home improvement store in Calgary.

Crews responded to the fire just before 4 a.m. at a Lowe's in the city's northwest.

The bodies were found inside the shed after the flames were extinguished.

Fire department spokeswoman Carol Henke says it's believed the three had been using the shed as a shelter.

She says the cause of the fire is not known.

The fire department and police arson unit are investigating.