The Better Business Bureau is warning consumers about a telemarketing scam involving operators who use the names of Canadian businesses to obtain credit card information for cheap vacations.

The calls claim to come from Karisma Hotels and Resorts in Mexico, and offer a six-day stay for four people for a total of $999 US. But when contacted by CBC News, Karisma Hotels and Resorts said they don't engage in any telephone marketing. The operators also sometimes say the deal is for WestJet or Air Miles customers.

"All the resorts are five stars or greater. We're working in conjunction with some of the Canadian airlines," said a telemarketer who called the CBC Vancouver newsroom on Saturday.

After a lengthy sales pitch, the operators inevitably end up asking for a credit card number.

"They will give you a six-digit approval code and this is what I tell all my customers to do: Be a wise consumer, and look at the back of your credit card. You're gonna see that 1-800 number for your credit card company. Please call them up, give them the six-digit approval code," the caller said.

"If I was to do you any harm, the last thing I would tell you to do is to call your credit card company. But I want you to do it because it will give you an instant peace of mind."

When a CBC News reporter expressed uncertainty at the price, the operator then tried to discount the package — first to $699, and finally offering to hold the deal for a $99 down payment.

'A very, very old scam'

WestJet says consumers in southern Ontario, the Metro Vancouver area and Alberta are being targeted.

"This is a very, very old scam. It’s a variation on a theme that’s been around for many years," said WestJet spokesman Robert Palmer.

"The scammers ... are essentially professional con artists trying to part you with your credit card information ... in the promise of a vacation package, which of course doesn’t exist."

Palmer says WestJet does not share the private information of its customers, and does not engage in any telemarketing.

"We’ve attempted to pursue these individuals and find out who they are, but unfortunately it’s a very sophisticated operation," he said.

"They use computer programs to generate randomly the numbers they call ... The same software scrambles and reroutes the phone number that they’re actually calling from so it’s almost impossible to trace the call."

Palmer says his best advice to consumers is to simply hang up.

"We’re really at the mercy of these con artists because it’s impossible to find out who they are, where they are," he said.

"The best thing that we can do is shine the light on them in the hope that they scurry back to the holes they came from."

'Who doesn't want to win a free trip?'

Mark Fernandes with the Better Business Bureau advises customers not to give out credit card information to strangers on the telephone.

"The credit card number, if you give it over to a scammer, one of two things can happen: the scammer will turn it around really quickly, make some large online purchases or maybe go to retailers on a fabricated credit card with your number," he said.

"Or the other thing is that it just gets compiled into a list with other credit card numbers that are sold through organized crime."

Fernandes says scams like this one are extremely common.

The telemarketers claim to be from a five-star resort in Mexico's Cancun region. (Israel Lea/Associated Press)

"People want to go on vacation right now, and who doesn’t want to win a free trip?" he said.

"Scammers know that this is something they can capitalize on and that people may be likely to give out their credit card information if they think they can get a free trip."

Fernandes advises people who think they might be victims of a scam to report it to their credit card company right away.