The Ontario Fire Marshal has been called to investigate a toxic blaze near Chatham’s downtown core.

Fire crews from stations #1, #2 and #7 were called around 1:12 p.m. Saturday to battle the blaze at a building at 61 Thames Street. The building is home to Church’s Army and Outdoor Military Surplus.

The fire sent thick black smoke into the air that could be seen for several kilometres.

Residents and retail workers in the area were told to evacuate, and stay away from the scene.

The Chatham Kent Fire Department also issued a notice stating “anyone living the area of Thames St. stay out of the smoke. If you are inside your home, please close all windows/doors and shut off HVAC.”

The area will remain closed for several hours.

No injuries are reported, but damage has been estimated at $550,000.

Still, Assistant Fire Chief Bob Davidson says fast action by firefighters prevented the flames from spreading to nearby buildings.

It’s estimated that work likely saved another half-million dollars in property.

There is no word on the cause of the fire. The Fire Marshall will help look into what could have started the massive blaze.

Davidson adds an “After the fire Reassurance Campaign” will take place, where firefighters will return to the area to visit residents, check smoke alarms and discuss fire safety planning.

The video below was taken by Chatham-Kent councillor Michael Bondy who uploaded it to his Facebook page.