NASHVILLE, Tenn. -- When a dog wandered into Stacey Russell's yard last week, she couldn't find its owner but wanted to make sure she found the dog a good home.

Video: Police Say They See Western Union Scams Every Day

"I just felt the people who had her before probably neglected her," Russell said.

She placed an ad on Petfinder.com, not thinking many would be interested in the pit bull/lab mix she named Cocoa.

Within hours, responses began pouring in.

"I was kind of shocked," Russell said. "I was like, 'Wow.'"

Russell decided she would give the dog to a woman named Mary Smith, who, in several e-mails, seemed very interested. A day later, Russell started receiving several $2,000 checks from "Mary Smith," asking her to use some of the money to ship the dog to California and the rest she should wire to a Nashville Western Union.

Russell's mom said she quickly realized this was a scam.

"It just sounded too good to be true," said Tricia Russell.

"If somebody asks you to send something back Western Union, chances are it's going to be a scam," said Metro police Lt. Mickey Garner.

Metro police said there are more crooks in this rough economy, and they're now seeing victims of this scam every day.

"Do not put that check in your account, simply because the bank will take the money out of your account if this turns out to be a counterfeit check," Garner said.

Police also said while some of the scammers may be overseas, some middlemen are local, as they pick up the cash from local Western Unions and send it to other countries.

"People who do this, they just need to get caught," said Stacey Russell.

Russell ended up sending the dog to Animal Control and said she is relieved she spotted the hoax before it cost her.

Police said those who believe they are being scammed can file a police report or simply shred the checks.