The family of a deceased US Postal Service employee said they found around 1,000 pieces of undelivered mail in the postman's storage unit.

Undelivered mail dating back 13 to 15 years has been found after the death of a US postal worker.

Around 1,000 pieces of undelivered mail from 2004–6 were found by the family of the deceased United States Postal Service (USPS) employee postal worker in Hawaii. There were also about 11,000 USPS return receipt postcards, which are used to tell residents that there’s a separate mail piece coming.

The USPS said the undelivered mail was mostly First Class and Priority Mail, newspapers and magazines. All of the mail was in sealed envelopes and packages, reported KHON2 News.

“We consider this mail to have been stolen. We don’t know why the employee committed this illegal act, nor do we know how or exactly when the mail was taken from a postal facility to the storage unit. We delivered the mail after conducting a thorough review of the pieces and the mail was properly prepared,” a USPS spokesperson told Hawaii News Now.

Officials have not publicly identified the worker nor where he or she worked, but most of the mail belonged to people living in the downtown Honolulu area.

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The USPS said most of the stolen mail has been returned and some had been sent to mainland addresses. They also said that people will know if their mail had been stolen and returned.

It will have a label detailing that this mail was delayed and will have a customer call number. Customers who have questions about this mail should call the local USPS office at 808-423-3428.

To avoid becoming a victim of mail theft, the USPS has given the following advice:

  1. To be safe, deposit your mail in a mail slot at your post office or give it to your USPS postal carrier;
  2. Don’t leave your mail in your mailbox for too long after it has been delivered. Ask someone you trust to pick it up for you if you will be travelling or have your mail held at the post office;
  3. Do not send cash in the mail. Checks or money orders are recommended;
  4. Missing a check or other valuable mail that you were expecting? Be sure to contact the issuing agency immediately, and
  5. If you have moved and changed addresses, be sure to immediately file a change of address the companies you transact business with. Don’t forget to have your mail forwarded via the USPS.

If you believe your mail was stolen, be sure to contact your local postmaster or postal inspector and file a formal complaint using PS Form 2016, Mail Theft and Vandalism Complaint.