A NZ Post investigation has revealed multiple items of mail have been tampered with, and in some cases taken, by a postal worker in Gisborne.
NZ Post service delivery regional manager Mario Kearney said an investigation was launched three weeks ago after a number of customer complaints were received.
"NZ Post takes delivering what people care about very seriously, so we are extremely disappointed to learn of this situation in Gisborne," Kearney said.
The number of items taken is still uncertain.
NZ Post staff are working with affected customers who have made contact.
NZ Post has also notified the Privacy Commissioner's office.
"Following a full investigation by NZ Post, disciplinary action was taken, which resulted in the worker being stood down.
"The matter may still be referred to the police," Mario said.
"We are extremely disappointed that on this occasion, the trust we place in our employees was not met, nor importantly, our customers' expectations.
"We ask any customers who think they may have been impacted by this to contact their senders and NZ Post."
If you have a specific question arising from this incident or would like to make a further complaint, contact NZ Post's Customer Care Centre via its website www.nzpost.co.nz, or phone 0800 501 501.