WINDERMERE, Fla. — Several Windermere residents said they were the victims of credit card fraud or identity theft.
They said they think thieves used the U.S. Postal Service's website to commit the crimes.
USPS allows customers to sign up for its informed delivery service, which sends them emails, showing them what mail is on the way to their home.
In one case, thieves opened a credit card and went on $10,000 spending spree. In two other cases, the victims discovered something was fishy before they were ripped off.
[ Read: At least 400 Orange, Seminole residents victims in identify theft scheme ]
Resident Bob Horner said he monitors his finances to watch out for suspicious activity.
"This is my PIN number for the credit card that they applied for," he said.
He said he received a letter from a bank about a new credit card with a $15,000 credit limit for which he never applied.
"This can wreck your credit ratings, and then you've got to justify in fact that it's not you, and then clean up all the back end of this stuff," Horner said.
He said he also received a letter from the post office verifying that he had signed up for informed delivery, which will send him an email with a preview of mail that's scheduled to arrive soon.
Horner said was unaware the service existed.
Diana Marini, who lives across the street from Horner, said she was also targeted by the scam.
"I saw somebody driving up, looking at the mailbox, and my mailbox was open," she said.
Marini said identity theft is a serious concern of hers.
"It could ruin your life, because you spend all your time defending yourself if you get into that situation," she said.
Another couple was also targeted in the same neighborhood, but they didn't realize it until the thieves opened a new credit card and spent almost the entire $10,000 credit limit.
Horner said he later intentionally enrolled in the service and now sees what letters are being mailed to him.
He said he has spoken with several people at USPS, but he is unsatisfied with the answers he has received.
The Orange County Sheriff's Office said an investigation is underway.
Channel 9 reached out to USPS for comment but hasn't heard back.