Woodbridge police are warning residents to be on the lookout amid a recent rash of mail thefts in the area.
Authorities said thieves are stealing business and personal checks from mailboxes, as well as from standalone USPS mailboxes.
The stolen checks are then fraudulently altered and cashed for large sums of money.
The police department is working with the U.S. Postal Inspector's Office to conduct an investigation.
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In the meantime, authorities say you shouldn't leave outgoing mail in your mailbox. You should also mail personal and business checks inside of a post office.
Police say to make sure you receive your mail as soon as possible, and frequently monitor your banking activity to detect fraud.
If you suspect any suspicious activity, you should contact the police department at 203-387-2511.