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DALLAS (CBSDFW.COM) – It’s a lesson some North Texans are learning the hard way. The warning, happening now during tax season, means a lot of folks are and will be watching their mailboxes.

Unfortunately, thieves also have their eye on your mail.

Some residents in one area of North Dallas say they have been victims of theft and in some cases had criminals steal checks, wash them, and cash them for big money.

Postal officials are again advising that the large, blue-colored drop boxes are the safest place for your outgoing mail.

There’s a new reason to resist the temptation to just toss outgoing mail in the curbside box. It only takes seconds for thieves to get it and be gone.

Beth Harp wasn’t expecting a delivery earlier this month. She did though get quite a shock when the mail carrier rang her doorbell and asked about an unusual package that had found its way into her curbside box.

“It was crammed full of open mail,” Harp remembered. “Somebody had been stealing mail out of mailboxes, opening them up and taking the checks out. It was people’s bills that they had been mailed out and all of the checks had been removed.”

Harp immediately tapped into Nextdoor – a private neighborhood social media network – to warn others.

The notice quickly hit a nerve with neighbor Stan Schultz, who has also had mail stolen. “They had laundered the check before Noon that day,” he said.

Schultz knew about the recent mail thefts. “I worry when I put my red flag up… that’s kind of a notice that I’m sending something out. Things have changed.”

A number of neighbors in the area are also investing in lock boxes. Dave Seibel recently purchased one. “This way, if we’re not here and the mail isn’t picked up for a day or two, it’s secure,” he said.

Harp didn’t have any checks stolen but has had mail with personal information in it disappear from her mailbox. She said, “I like to think that most people are good people and they’re all just trying to get by. But, there are people who aren’t working really hard to get by. They’re working really hard to take advantage of the rest of us. And it’s sad to have to make that adjustment.”

Postal inspectors stressed that they prosecute anyone caught tampering with the mail but they need your help to let them know if you suspect something. Call 877-876-2455 to report any problems.

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