A witness says he heard explosions after a fire broke out at a business in an industrial area north of Regina.

Dark smoke billowed into the air as fire crews responded to the scene at 301 Sherwood Road late Monday afternoon.

Neil Fairbairn, the office manager at construction equipment supplier ModSpace, called 911 after he saw the flames.

“I was doing my paperwork in my main office there and I heard a noise, just like the wind blowing the dirt on the windows, that sounded ominous, so I looked out a little bit further and the back-corner loading dock was on fire,” Fairbairn said.

“Propane tanks started exploding… and I got the heck out.”

Roads in the area were closed as firefighters brought the blaze under control. People were being moved away from the scene because officials believed smoke from the fire may be toxic.

There was no word on what caused the fire.