Mail that had not been delivered was found in a recycling container in Union Saturday, police said.
In a release, Union police said the mail was found at a home on Elberson Court. An "abandoned" USPS vehicle was found nearby, police also said.
Police held the mail until it could be picked up by investigators from the United States Postal Service.
London Mulcahy, a spokeswoman for the USPS Office of the Inspector General, said the vehicle was not abandoned but had broken down and was later retrieved by USPS personnel.
But she did say Friday that the inspector general is investigating the discarded mail. Mulcahy did not release any additional information, citing the ongoing investigation.
Residents in several Union County towns have complained that mail arrives very late or not at all. Mulcahy urged the public to lodge complaints or concerns at the OIG website.
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