Police suggest not mailing personal checks or gift cards and to use electronic bill payment to circumvent the thieves.
Three men were arrested in early September, accused of using the setup to snag mail from a dropbox near the New Milford Post Office, the Bergenfield Daily Voice reported.
Less than a week later, two more men were arrested when police found them parked in a post office parking lot at 1:30 a.m. Police said they found mouse traps with a string glued to them in both cases, the newspaper reported.
It has become such a problem over the past year that in some cities the U.S. Postal Service started installing new mailboxes that have a mechanism that latches onto the letter once it is put in the mailbox. The USPS did not say how the system works, The New Jersey Record reported.