A mail carrier working in Randolph was robbed of their master key Wednesday.

The postal worker was at the Rosemont Square Apartment Complex around 12:30 p.m. when two masked men dressed in black physically assaulted him, injuring his ribs and sides, Randolph police say.

The worker’s mailbox master key or “arrow key” was stolen during the alleged assault. The key opens drop-off boxes and multi-mailbox panels at apartment complexes. When one is taken, it can lead to a spike in checks, credit cards, and gifts stolen from the mail.

This is the second time this year a mail carrier was robbed in Randolph. In March, a USPS letter carrier was delivering mail in the vicinity of Canton Street when they were approached from behind by a robber.

Earlier this year, 25 Investigates reported the postal service was investigating robberies of master keys.

Robbery of Boston letter carrier part of ‘mail theft epidemic’, according to Postal Police Union

At least six other postal workers have been robbed in Boston since 2022, according to data from police and the USPS.

The United States Postal Service provided the following tips residents can use to protect themselves and their mail:

• Deposit outgoing mail into USPS Blue Collection Boxes before the last collection or inside the Post Office.

• Do not send cash or coins through the mail. Use checks or money orders. Ask your bank for “secure” checks that are more difficult to alter.

• If you see any suspicious behavior around mailboxes, or believe your mail has been stolen, please notify Postal Inspectors.

Customers can submit reports at www.uspis.gov or by calling the USPS at 877-867-2455.

This is a developing story. Check back for updates as more information becomes available.

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