GUELPH -- Guelph police are warning the public about a Bitcoin scam, after two similar incidents in two weeks.

Police say a 68-year-old man contacted them Saturday afternoon, who told them he had been contacted by someone claiming to represent the Canada Border Services Agency.

He was told a package with his name on it had been intercepted at the border and inside they found illegal substances.

He was told to deposit $3,900 into a Bitcoin ATM while the caller was on the line.

The man said he got suspicious when the caller demanded he get more money from a line of credit and hung up.

Less than two weeks ago, police say a 27-year-old Guelph woman lost nearly $8,000 in the same scam.

Police are warning the public that payments made by Bitcoin or other crypto currencies are nearly impossible to trace and they have advice to help recognize a scam.

They say you should never give any information to a caller you don’t know, and don’t click on links provided in texts or emails from anyone you don’t know.

If the caller claims to be from an agency, like Canada Border Services or the Canada Revenue Agency, hang up, look up the number yourself, and call the agency back.

Police say scam callers will use many methods, including threats, to try to force you to act quickly, and that no government agency will demand payment by gift cards or crypto currency.