Wellington County OPP say a trailer loaded with $500,000 in webcams was stolen near Guelph on Monday.
At around 1 a.m., surveillance video shows a transport truck pulling the trailer away from a business on Whitelaw Road in Guelph-Eramosa Township.
The trailer was later found empty on Columbia Street East in Waterloo Region.
There was also a light-coloured car, possibly a Ford Focus, seen on surveillance driving slowly past the business before the transport truck showed up, police said.
OPP have released photos of the car and the transport truck.
Anyone with information is asked to call investigators at 1-888-310-1122. Anonymous tips can be left with Crime Stoppers at 1-800-222-8477.