Officials say a prank in Cape Breton is to blame for millions of dollars’ worth of damage at a local Walmart.

Police believe a prankster set off a marine smoke flare in the North Sydney store on Nov. 6. Orange smoke filled the building and covered the inventory as staff and customers were left racing for the exits.

Marine smoke flares create a large orange cloud of smoke when triggered and are designed to be used in emergency boating situations for easy detection.

The store has been closed ever since.

Walmart Canada told CTV Atlantic the company was forced to haul away truckloads of goods on Friday as the smoke created a sticky residue on products that can’t be washed off.

Under normal circumstances, Walmart said the company would donate products that can no longer be sold to charity, but in this case, the damaged goods are too far gone.

With most of the inventory unsalvageable, total damage is estimated in the millions of dollars.

Officers believe the flares were stolen from a nearby abandoned commercial building.

A similar prank also happened at a nearby high school, but the damage was minimal and the students were able to return to class the next day.

In both incidents, officials found flare canisters in the buildings.

Walmart Canada says it hopes to reopen the store in time for Black Friday.

With a report from CTV Atlantic’s Ryan MacDonald