GROVEPORT, Ohio (WCMH) – As police in Groveport, Ohio investigate after mailboxes outside a post office were broken into, a security expert said this type of theft is a growing problem across Ohio and the country.

Police said the theft of the blue mailboxes happened overnight Monday, with everything inside the boxes being stolen.

On Monday night, one of the boxes was still being used while the others had yellow “Do Not Use” signs attached to them.

Mail theft, specifically involving stolen checks, is a growing problem around the country.

Dr. David Maimon is the director of the Evidence-based Cyber Security Research Group at Georgia State University.

He said there has been an explosion of stolen check sales on the dark web, with many of those being taken from mailboxes.

“It’s mindboggling to see what we are seeing,” Maimon said.

In October of 2020, the group recorded 114 checks stolen nationwide in one week. Now, that average is about 2,000 a week. On just the channels the group looks into, Maimon estimates $50 million a month is being stolen nationwide.

“The industry of stolen checks is spreading like fire in this country,” Maimon said.

According to Maimon, criminals are using chemicals to remove information on the checks, essentially creating blank checks, a process called washing.

“So it’s not only that we see them selling the checks; we see the entire ecosystem of check fraud, unfortunately, in the United States on these platforms,” he said.

While Maimon can’t definitively say what happened in Groveport is linked to what his group monitors, Ohio is the 10th highest state in the volume of checks the group finds.

“It’s definitely a problem,” he said. “We see many, many checks coming from the city (Columbus). We see many, many checks coming from the surrounding of the city. Folks should take this into consideration and not leave their mail. They should not send their checks using the blue mailboxes.”

In addition to Ohio, the top places where the group is seeing a lot of check theft are New York, New Jersey, Pennsylvania, Delaware, Texas and Washington D.C.

Police said a possible suspect vehicle in the Groveport theft is a silver Dodge Dart with a missing driver-side rear hubcap.