If you ever send cash, a check or any financial statements through the mail, you probably want to pay attention to this.

Thieves are now targeting blue U.S. Post Office mailboxes all over New Jersey so they can get their hands on letters and steal the contents.

Greg Kliemisch, the postal inspector for the Newark Division of the U.S. Postal Inspection Service, said crooks are employing a variety of methods, including sticky rodent an insect traps.

“We’ve also seen signs of a glue-like substance on a mailbox door that would prevent the mail from dropping into the mailbox," he said.

Some thieves wait until it’s dark and no one is around. But in some cases, “we’ve actually even seen individuals prying open the mailboxes to gain entry to people’s mail," he said.

He noted many mailbox fishing crimes have taken place in Middlesex, Union, Passaic, Bergen, Essex and Hudson counties, but officials believe criminals and copycats may be branching out and committing these thefts all across the Garden State.

So what are the crooks looking for?

“The contents could include gift cards, checks written upon a financial institute, cash.”

Kliemisch said to safeguard your mail, deposit letters in a mailbox before the final pickup time, which would be noted on the box.

“So looking at a collection box, if the last pickup time is at 5 p.m. we ask that if you’re coming to a box and it’s 5:01, if you could wait till the next business day to deposit your mail or find an alternate location.”

He added if you go to a mailbox and notice any kind of sticky substance on or in the box, “first off, don’t put your mail in that mailbox. And you’re asked to contact the Postal Inspectors at 877-876-2455.

If people see any weird or suspicious activity around a mailbox, "first and foremost, they reach out to their local police department.”

Kliemisch noted it’s always important for people “to monitor and review their financial statements regularly, both bank and credit cards, to ensure that no suspicious activity has occurred.”

He added if you mail someone a check and they don’t receive it, check your records “to make sure that nothing was altered to be paid to another party that you didn’t intend for.”

He stressed the Post Office is not recommending that you avoid putting envelopes in a blue mailbox.

“We’re just asking that our consumers are using that last pickup time as a cutoff time to drop anything into that mailbox.”

Courtesy U.S. Postal Service

He pointed out yellow decals are being placed on more and more mailboxes, warning people to not drop letters into the box after the final pickup time of the day.

Postal officials say they’re working on security upgrades to mailboxes, but they would not specify what that may or may not entail.

You can contact reporter David Matthau at David.Matthau@townsquaremedia.com

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