The RCMP says several Calgary residents tricked 24 elderly or disabled Americans out of about $3 million over a three-year period by telling them they had won a lottery.

Police released more details Thursday of what they're calling a cross-border telemarketing scam.

Between 2005 and 2008, the victims were contacted by letter or phone and told they had won a lottery or sweepstakes but were required to pay taxes, administration fees or lawyers' fees before they could collect winnings, which didn't exist.

One person sent in between $500,000 and $1 million, with the scam collecting about $3 million in total, said RCMP Insp. Frank Smart.

Some people lost their life savings, have been ostracized by family or have been forced to remortgage their homes. Others in their 70s had to return to work, said Smart.

The 24 victims all lived in the United States, but there were hundreds more on a telemarketers-type list, which can be purchased online in that country, he said. That may be why Canadians were not targeted, Smart speculated.

A police investigation began in late 2006, when two undeclared parcels containing $10,000 in cash were delivered to the Calgary suspects.

Investigators have arrested four people from Calgary, one from Burnaby, B.C., and one from Toronto. Canada-wide arrest warrants are outstanding for three other suspects who police believe are in the Calgary area.

On Wednesday, RCMP announced 261 charges had been laid, including money laundering, fraud over $5,000 and conspiracy to commit fraud.

With files from Zulekha Nathoo