By CBS3 Staff

NEWARK, Del. (CBS) — In Delaware, Newark police have a warning about checks in the mail. Over the last five weeks, thieves have stolen at least $50,000 worth of checks from the United States Postal Service.

The victims say their checks were dropped off in various mailboxes around Newark.

The thieves altered the checks then cashed them at various locations nationwide.

Authorities are investigating exactly how those checks are being stolen. They recommend making payments electronically whenever possible.