Debris from the explosion — including refrigerator and freezer parts, paper towels and some food items — was scattered in the vacant lot where it sat. The trailer of the truck was ripped apart, but there were no reported injuries.
Staff Sgt. Chuck Konkel said the explosion happened at about 4 a.m. Friday.
Konkel said the explosion, which occurred in an area where many people could be during daytime hours, caused about $30,000 in damages. The blast was powerful enough that police officers working two kilometres away heard and felt it.
CNE general manager David Bednar said the exhibition requires vendors to follow strict regulations, and said in his 15 years with the fair he doesn't believe an accident like this has ever happened.
"Every single day I've got a third-party contractor, with five engineers or six, on site every day, looking for trip hazards, looking for equipment not connected correctly," he said.
The vendor operating the trailer that exploded hasn't returned calls from CBC News.
Depending on the results of the investigation, the fire marshal could press charges.
Also on HuffPost