Toronto police and the fire marshal's office are investigating after an explosion destroyed a portable concession stand at the CNE early Friday morning.

Police and fire officials believe a propane tank exploded within the food stall, creating a large debris field, in a parking lot near Ontario Drive and Princes' Boulevard shortly before 4 a.m., when the grounds were closed to the public and few people were around.

No injuries were reported.

Had the incident occurred when the grounds were open, the outcome could have been disastrous.

“I think we’re very fortunate it happened so early in the morning and it’s pretty much in an isolated area,” police Sgt. Mark Morris told CP24's Nathan Downer.

Toronto Fire Services Capt. Mike Strapko said a propane cylinder inside the trailer had an open valve, resulting in an explosion that caused about $15,000 in damage.

Strapko said the food trailer that was destroyed was about eight-by-10 feet in size.

A trailer and a van parked nearby sustained some damage.

As per police protocol, bomb experts were brought in to inspect the scene to determine if there was any additional threat to the public.

A CNE spokesperson told CP24 the grounds are open as usual.

This is at least the third incident police are investigating at this year's CNE.

Earlier this week, a 15-year-old boy told police he was sexually assaulted by a man in a washroom at the Direct Energy Centre. No one has been arrested.

Late Thursday night, a male was stabbed near the Ferris wheel at the fair's midway. He was taken to hospital to be treated for non-life-threatening injuries.

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