Saskatchewan Telecommunications is warning customers about a scam where crooks piggyback onto their phone lines for free long distance.

Some customers have already been caught, while others have had some close calls.

It involves the *72 service that lets customers forward phone calls.

Scammers have been phoning in, asking unsuspecting phone customers to transfer calls to long distance numbers. Then the customer gets stuck with the bill. As well, the customer can't get incoming calls on his or her own phone.

Saskatoon's Darryl Kehoe was recently vacationing in Mexico with his wife when someone got hold of his home phone number.

"Of course, they phoned our house," he said.

His parents were in the house babysitting their children when the phone rang.

The person on the other end told them he was a Mexican police officer and said there had been a serious or fatal car accident.

Immediately, his father Art Evenson thought it was his son and daughter-in-law who had been hurt.

But it was a just a story concocted by a scammer.

"That's terrible," Evenson said. "When you take money out of someone's bank account or something that's one thing, but the emotional distress that you put people through, not knowing what's happening, that's one of the worst tricks you can play."

The scam artist told Evenson to call a long distance number beginning with *72 to contact a police officer in Mexico.

Fortunately, it didn't work. Kehoe didn't subscribe to the call forwarding service.

But others have been stuck with extra charges on their phone bills.

"It can result in significant charges once the call forwarding is activated," said Andy Tate of SaskTel. "You're responsible for all long distance charges until it's deactivated."

Saskatoon police said finding phone scam artists is difficult. One way to protect customers is simply by spreading the word about what's happening, they said.