Durham police say they've found what appears to be a confinement room in an old abandoned farmhouse east of Toronto.
Police say the room in the northwest Pickering home was recently built and looked like it was "solely designed to hold someone captive."
Investigators are now trying to figure out if the room was used to confine someone or designed for another purpose.
One possibility, they say, is that it may have been built as a prop for an amateur filmmaker.
Contractors surveying the property stumbled upon the room in the basement of the farmhouse, which is slated for demolition, more than two weeks ago.
Durham police spokesman Dave Selby says the home has been abandoned for so long that the focus isn't on the original owners, but on anyone who may have been seen driving in the area or any other suspicious activity.
"They're obviously down there because it's somewhere where no one would check," said Selby.
"You could stick someone in this room and lock them in."
Police haven't ruled anything out, he added, but have yet to determine if anyone was ever held in the room.
"Our forensic guys went down and took all kinds of samples of anything they could find to figure out if it was used and how it was used," he said.
"But at this point it's still under investigation, and we really don't know if it was used for a criminal purpose or not."
Anyone with information is asked to call Durham regional police or Crime Stoppers.