By Tim McNicholas

UPDATED 09/23/21 11:13 p.m.

PARK RIDGE, Ill. (CBS) — A man was arrested in Dolton last week in connection to a series of mail thefts from blue U.S. Postal Service collection boxes.

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Postal inspectors said a tracking device placed in a bin inside one of those boxes is what led authorities to Kelvin Dortch Jr., who stands charged with theft or receipt of stolen mail.

CBS 2 has been reporting for months on mail problems at the post office in Park Ridge, and now we’re learning about the elaborate plan by postal police to catch the thief.

Last week, CBS 2’s Tim McNicholas reported on federal and local police investigating a pattern of check fraud in northwest suburban Park Ridge after several people who were out several thousand dollars.

There were claims that someone tampered with checks after mailing them in Park Ridge, increased dollar amounts, and altered recipient names.

According to the charges against Dortch, surveillance cameras mounted outside the Park Ridge post office caught someone breaking into the blue drop boxes five times in the past four months.

The thief had a postal key that they used to open up the box, and steal the mail.

It happened a sixth time a few days ago, but this time, postal inspectors had installed a GPS tracking device in the bin inside the drop box.

Investigators say the thief took the bin of mail from a box outside the Park Ridge Post Office to a home in Dolton.

Court records say that’s where postal inspectors found their tracking device, along with “mail matter addressed to other USPS customers,” and Dortch.

No one answered the door at the home today.

A charging document says he was caught on camera stealing the mail around 1:40 a.m. on Sept. 15.

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That’s just two days after a CBS 2 report aired detailing a pattern of mail theft and check fraud in Park Ridge.

“You have X amount of people that touch the mail, and it could be a non-employee, but try and get to the bottom of it,” said Park Ridge Baseball and Softball President Garry Abezetian, one of multiple victims over the past two years saying someone altered their checks—changing the names and even the dollar amount—after they mailed them in Park Ridge.

Dortch is only charged with mail theft so far.

“I don’t believe that it could have been somebody working alone,” said another victim, Susan Costello.

She hopes the arrest brings investigators closer to discovering who stole and altered her check back in July.

“I’m just glad that it came to the forefront, so that nobody else has to go through—I mean hopefully this is the end that nobody else has to go through what we’re going through now,” Costello said.

The investigation isn’t over, and court records don’t say whether Dortch was the thief in each case.

Authorities said, in each theft, someone used ”either an authentic or counterfeit” postal key to open the mailbox.

Dortch is not a postal employee and detectives would not say how Dortch or anyone else could have gotten such a key.

Meanwhile, after CBS 2’s Tim McNicholas got to the scene, he noticed something else – mail poking out from the bottom of the same rusty blue box where the theft happened. At the time, McNicholas asked the Postal Service what happened and did not hear back.

But on Thursday, we returned to find those mailboxes wrapped in yellow tape.

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Spokesman Tim Norman released the following statement:

“These collection boxes are in the process of being replaced. When collection boxes are damaged or in need of repair, the Postal Service removes the collection boxes from service until replacement.

“The Postal Inspection Service and the United States Postal Service take the security of mail very seriously. Customers can participate in our efforts to keep the mail safe by reporting any suspicious activity around our blue collection boxes. And if your viewers believe they have been a victim of mail theft, they should contact Postal Inspectors at 877-876-2455.”

Tim McNicholas