HAMMOND, Ind. (AP) — The U.S. Postal Service is investigating how more than two dozen pieces of mail ended up being dumped into a trash can outside a home in northwestern Indiana.

Al Lebioda tells The (Munster) Times he discovered the letters on Sunday in an alley behind his Hammond home. All but two of the letters were unopened, with one from the Indiana Bureau of Motor Vehicles.

The case was turned over to the U.S. Postal Service-Office of Inspector General, which conducts internal investigations of the post office. Post Office spokesman Jeff Arney says the investigation is continuing.

Officials will investigate to determine if a postal employee or someone else may have been involved in the removal of the mail.