Sergeant Michael Palmer said police became aware of an issue when someone reported their new credit card never arrived in the post.
Despite the card not arriving, new charges were being added to it.
Police executed a search warrant at a Hamilton address this week where they found hundreds of letters and documents. Palmer said police were establishing the extent of the offending.
Officers arrested a 28-year-old man and charged him in relation to the suspected years-long mail theft scheme.
He was due to reappear in the Hamilton District Court on May 31.
Meanwhile, police offered tips on how to protect against mail theft and asked anyone with suspicions about someone loitering around houses or looking in mailboxes to report it.
“There are a number of actions people can take to protect themselves from mail theft, including sending parcels to a work address or ensuring you will be at home when they arrive,” Palmer said.
Provide clear delivery instructions for couriers to leave a package safely hidden or secured within your property.
Install security cameras and/or security camera messaging near your letterbox or the front of your property.
Where practical, consider ‘click and collect’ over delivery.
“If you see any suspicious activity, such as unfamiliar people loitering around properties or looking in mailboxes, please contact police immediately,” Palmer said.
Raphael Franks is an Auckland-based reporter who covers breaking news. He joined the Herald as a Te Rito cadet in 2022.