Police in several Connecticut cities and towns have been issuing warnings about checks being stolen and altered.
Westport police said Friday morning that they are seeing an uptick in “check washing” cases and they are investigating.
Check washing happens when the ink on a check is removed and the check is rewritten for a larger amount.
Westport police said checks that have been put in mailboxes to be picked up by a postal employee are stolen and someone changes the payee and check amount and then cashes or deposits it at a bank.
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They said checks that end up being “washed” have been stolen from both residential and United States Postal Service mailboxes within Westport.
Several other police departments have seen this happens as well, including Berlin, Coventry, Fairfield, Glastonbury, Simsbury and West Hartford.
Police are warning residents to be cautious.
Police urge people to avoid placing checks they have written directly in free-standing mailboxes. Instead, make the transaction electronically or mail the check from inside the post office during business hours.
If you're mailing a check, police advise you to check your bank account often, looking for any suspicious behavior. People should also look out for any late notices from a creditor expecting payment - police say this may be the first sign of a stolen check.
The Postal Inspector and Postal Police are also involved in investigations, authorities said.