Police in Ontario, Canada say they will hold a man who allegedly swallowed a $20,000 diamond for as long as it takes for him to produce the evidence.

It has been nearly a week since Richard Mackenzie Matthews, 52, is alleged to have switched a diamond at Precision Jewellers and swallowed the real one. 

Matthews has been held at police headquarters while they wait for the 1.7-carat stone to pass through his system.

Sgt. Brett Corey said Thursday that Matthews has gone to the washroom numerous times, but the diamond hasn't passed. 

Corey says a recent X-ray showed a pair of fake diamonds, or cubic zirconiums, stuck in the man's intestines but because a diamond is translucent, it isn't visible.

He says the suspect is eager to get the ordeal over with and is co-operating. In the early stages, Corey says Matthews was being given laxative type foods, but is now being fed whatever he wants, in an effort to get things moving. 

Matthews is charged with theft and breach of court conditions, and is also wanted on warrants in Toronto. 

“We’re still waiting him out, but at this point, we don’t have anything to show for it,” Corey told the Toronto Sun.

The Windsor Star newspaper said the grim task could not be forced on a rookie detective. 

“It’s not like a hazing or ‘you’re the junior guy, in you go,’” Deputy Chief Jerome Brannagan told the newspaper. "Whoever is involved in that has to be somebody who is qualified to give evidence in court. They’re going to have to articulate what happened, how it happened, how they recovered it. The chain of evidence has to be maintained.”

The Associated Press contributed to this report.

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