POLSON – Responding to a recent spree of check thefts, cops are asking Polson residents to keep an eye on their mailboxes.

Check theft and “check washing” are gaining popularity among the criminal element, said Lake County Sheriff Detective Kim Leibenguth.

Criminals cruise neighborhoods that have mailboxes with red flags up, she said. They steal checks and then put them through a chemical process called check washing that erases the payee’s name but retains the signature.

They cash forged checks, take money intended for others and repeat the process.

Check fraud is a federal offense and local law enforcement is working with the United States Post Office in this investigation.

Leibenguth said the safest way to send checks is to bring them to the post office or put them in your mailbox just before pickup or delivery.

The Lake County Sheriff’s Department asks anyone with information about check fraud to contact the office at 883-7329.