A scam that loads hefty fees onto your phone bill is resurfacing across Canada.

The fraudsters behind the so-called “one ring scam” place calls that appear to originate overseas and hang up quickly. Curious victims return the anonymous missed call and inadvertently agree to fees that get piled onto their monthly bill.

Marian Henry with the Better Business Bureau of Manitoba and Northwest Ontario said the charges, which are similar to ones you would receive for calling a 1-900 number, can cost hundreds of dollars per minute.

“When they do call back, it puts them through to a pay-per-call type of scenario where there’s a cost involved to initially be connected, as well as a cost-per-minute once you’re on that call,” she told CTV Winnipeg last week.

Henry said callers are often greeted by waiting music or a pre-recorded message.

“The longer they are on the call obviously the more expensive the call could end up being, sometimes $400 a minute,” she said.

Debbie Leah said she received a “one ring” call last Monday. It was almost midnight when her phone rang. She didn’t recognize the number and the caller did not leave a message. An internet search indicated the number was from the West African republic of Mauritania.

“I’ve never even heard of the place it came from,” she said.

The Canadian Anti-Fraud Centre has said the calls have targeted people across Canada. The agency advises against returning missed calls from unfamiliar numbers and said it is important to check phone bills for unusual charges.

The return of the “one ring scam” comes as police in Toronto grapple with another type of phone-based fraud where victims are convinced to transfer money into a fraudster’s account. Police issued a warning last week after five people were bilked out of a combined $5.1 million.

Henry said blocking suspicious numbers is not enough to protect against fraud, and reminds people to be vigilant whenever an unknown party initiates contact over the phone.

“The numbers tend to change all the time, so blocking the number isn’t really helping. You could receive 10 calls in a week. And they could all be from different phone numbers,” she said.

With a report from CTV Winnipeg’s Gabrielle Marchand