An accompanying message also talked about Ebola, he said.
The package, also including a document and a small plastic bottle containing a small amount of liquid, was secured by the Army's explosive ordnance disposal team shortly after 6pm.
It had now been sent to ESR (Environmental Science and Research) for forensic testing.
An investigation was now underway that to establish any links between the packages.
An Auckland police spokeswoman said the Fire Service attended the Herald incident, along with police, while health officials were briefed.
All precautions were taken as to the real and perceived risks, the spokeswoman said.
Herald owner NZME. said: "An unaddressed package was sent to the New Zealand Herald offices in Auckland today. Protocol was followed for a matter such as this and it is now a police matter."
Police said the bottle would be swabbed for DNA and checked for fingerprints before being sent to Melbourne for testing.
"Police are often called to deal with and investigate the origins and contents of suspicious packages," Detective Inspector Scott Beard said.
The "vast majority" of them turned out to be benign but police didn't take any chances, he said.
New Zealand health authorities said there were no Ebola cases in New Zealand.