CHICAGO, IL (WOWO) A growing form of mail fraud known as check washing is drawing concern from financial experts and law enforcement as incidents tied to intercepted mail continue to increase across the country.

The scam involves thieves stealing paper checks from mail systems and then chemically or physically altering them, changing the payee name and sometimes the payment amount before depositing or cashing them, according to KHOU 11 reporting.

Experts say victims often do not realize the fraud has occurred until money is missing from their accounts and intended payments are not received by businesses or individuals.

Legal and financial professionals say prevention is critical because once a check is altered and successfully cashed, recovery can be difficult and often requires a formal investigation.

An attorney who has handled check fraud cases, Tate Williams with Hilder & Associates, says criminals frequently manipulate both the written recipient and the dollar value to redirect funds.

He said many cases begin with simple mail theft from unsecured residential mailboxes or public collection boxes, which remain common targets.

Financial industry officials say check fraud tied to mail theft has increased significantly in recent years, with hundreds of millions of dollars reported stolen in a short period as paper-based payment systems remain vulnerable.

A banking executive, Kevin Monk, says institutions are seeing similar patterns across the country, with customers increasingly reporting altered checks and unauthorized withdrawals.

He said banks are expanding training for employees to identify suspicious or modified checks earlier in the processing chain, though prevention remains a challenge due to evolving tactics used by criminals.

Experts recommend several steps to reduce risk, including using gel ink pens when writing checks, keeping checkbooks secured, and mailing checks directly from post office locations instead of residential mailboxes.

They also advise immediate action if fraud is suspected, including contacting banks quickly, filing a police report, and reporting incidents to postal inspection authorities to improve chances of recovery during the investigation process.