So far, more than $3,000 in dozens of checks have been stolen or "fished" out of the large boxes, said Stamford Police Sgt. Steve Perrotta.
"I suggest if residents are mailing important payments or sensitive mail to walk inside the Post Office and hand the items to a clerk," Perrotta said.
That's because the thieves are hitting boxes in different locations, including very busy ones such as a box in front of Starbucks.
"It doesn't seem to matter if they are busy or isolated when it comes to using the box," he added.
The department found out about the "fishing," problem when residents were notified they owed money on their utility bills when they had mailed checks, then the checks were cashed made out to a different entity and for a different amount.
He declined to say how they "fish" saying the Post Office has requested they don't give out the information. But he did say it was a pretty easy, old-fashioned technique that has been done for years. This is the first time in at least five years that it's been taking place in Stamford, he added.
Changing the checks is also pretty easy, he added. With the bad guys using acetone to erase the name and amount and then write in new amounts.
Postal officials are asking residents to report any sticky substances on the edges of mailboxes to your local post office or by calling postal inspectors at 877 876-2455.
Anyone who believes they have been the victim of a mail theft can report it online here.
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