CALGARY -- Crews were called to a large grass fire in northwest Calgary on Sunday afternoon.

Firefighters were called around 3 p.m.

It’s believed the blaze began at a rural property in Rocky View County.

Officials said roads acted as a barrier to keep the flames from spreading. Three area farmers also helped contain the fire.

No structures were threatened, and there were no reports of injuries.

Investigators are now trying to determine how the fire started.