Evesham Township Police and USPS investigate mail thefts in Marlton, New Jersey

MARLTON, N.J. (CBS) — Mail is missing in Marlton. Police say they have seen a significant increase in mail-related fraud cases this summer.

Thieves are after your hard-earned money and if you don’t pay attention it could cost you thousands.

Evesham Township Police say they have fielded about 20 complaints of mail theft since June. The mail is being stolen from the blue collection drop boxes behind the post office and in the neighborhoods.

“Someone is obviously keeping an eye on it and getting into it successfully,” one person said.

A monthly credit card payment one woman put in the mail nearly wiped out her bank account. She says she dropped a check into a collection box behind the Marlton post office in July but quickly learned the check was stolen.

She asked us to hide her identity because her name and address are still out there.

“Our check we wrote for this company showed up with someone else’s name and a different amount but still our signature on it,” she said.

CBS News Philadelphia learned she is one of about 20 victims across the Marlton area.

Investigators are not detailing how the mail is being stolen from the collection boxes but they say thieves are primarily looking for checks. Many times, they wash the checks with chemicals to remove certain information.

“I don’t know if they have cameras on that mailbox but they better get one,” Gene Mosca said.

The U.S. Postal Inspection Service says if you believe a check was stolen through the mail, contact your bank or credit card company right away. They also encourage you to submit a complaint online and recommend dropping off your mail and any checks or payments inside the post office.

“I just think it’s safer just to go inside,” Mike Berry said. “Since I just found out about this, I’m going to continue to do that.”

“Some people are reporting that they have multiple bills missing still that are not accounted for, that’s scary that their checks are floating out there,” she said.

Here’s another tip, routinely check your online banking to make sure everything adds up.

Evesham Township Police and the U.S. Postal Inspection Service say they are actively investigating these mail thefts.