Bemidji Firefighters spent six hours battling a fire at Northwoods Ice on Memorial Day.
Crews responding to the scene reported heavy plumes of brown smoke around the eaves and doors of the building.
Though unable to make entry due to high heat and heavy smoke, firefighters learned that a large amount of anhydrous ammonia was stored inside the building and was beginning to leak.
Anhydrous ammonia is a commonly used refrigerant, among its many uses, but is toxic when inhaled.
Crews were removed from the scene for decontamination and evacuation orders were temporarily placed nearby the facility.
The Minnesota State HazMat Team from Grand Rapids isolated the leak, with the scene declared safe, but was still under monitor Tuesday afternoon.
The structure and its contents suffered extensive damage in the blaze deemed accidental.
No injuries were reported but several firefighters were monitored for signs or symptoms from the chemical exposure.