Details of the robbery are scarce, but the USPS released a reward poster that said the two suspects approached the carrier with a gun drawn around 3 p.m. on Saturday, Dec. 10, in the Orchard Lane area.
A home surveillance photo shows two people dressed in all black walking in the area at the time of the robbery.
A man who lives in the area told WCVB that the mail carrier had served that community for years and is set to retire soon.
"She's very nice, very friendly," he said. "She sometimes gives the dogs treats when she comes to the door. She's been our carrier for several years. I see her every day. I heard she was about two weeks away from retirement."
The US Postal Inspection Service asks anyone with information about the armed robbery to contact agents at 1-877-876-2455. Say "law enforcement" and reference case number 3927109 when prompted. All personal information is kept confidential.
Postal officials did not say what was stolen or how many residents were affected by the theft.
The Melrose Police Department is also working on the case.
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