Toronto police are warning the public of a "possibility of explosions" after charging an appliance store owner for allegedly selling industrial gas ovens with counterfeit safety certificates.

Investigators said the owner of the three Kitchen Queen appliance stores is alleged to have sold a "large number" of ovens to restaurants, caterers and some homeowners in the city.

Toronto Police Staff Supt. Byrce Evans said the ovens had counterfeit stickers suggesting the appliances had been Canadian Standards Association (CSA) approved.

Evans said there was a "bonafide" safety risk for anyone who purchased ovens with the falsified stickers. The ovens do not comply with Canadian safety standards, he said.

"Basically, they are fire hazards with the possibility of explosions being hooked up to natural gas," Det. Rob Whalen said at the Friday morning news conference.

Police said it appears that at least 300 ovens were sold by the accused over the past year to residents of Toronto and the rest of Canada. He said the ovens were purchased in India and assembled in Canada.

Fittings were added to the ovens so they could be hooked up to natural gas lines. Some of the fittings were made from pipes intended to carry water, not gas, police said. The ovens were then sold at Kitchen Queen locations on Gerrard Street, Danforth Avenue and Markham Road.

"If you have purchased or have fuel-fired kitchen equipment - natural gas or propane - from Kitchen Queen, stop using the equipment immediately and contact your fuel distributor and the Technical Standards and Safety Authority," police said in a statement.

Whalen said police have recovered approximately 100 of the ovens so far.

In addition to the ovens, Whalen said police recovered additional fire hazards, and a "large amount" of improperly stored fireworks.

As a result of a joint investigation between CSA officials, police and firefighters, 57-year-old Gautham Mashetty has been charged with possession of property obtained by crime and passing off wares. He will be appearing in court in January.

The investigation is ongoing, and anyone with questions or more information is asked to contact police at 416-808-7298 or email frauds@torontopolice.on.ca.

Emergency workers and natural gas service providers across Canada have been notified due to the safety risk, police said.