Armed officers are guarding the entrance to an apartment complex on Gore St in the sity.
An RNZ reporter saw about five police cars and several ambulances at the scene .
Two police officers were guarding the door of Auckland Harbour Suites, questioning witnesses or residents.
In a statement, police said at least one person had been injured.
"At this stage, we do not believe there is a wider risk to the public in relation to this incident."
Inquiries were ongoing.
Police cars had arrived about 7.15am and officers armed with assault rifles made their way to the apartment building.
One resident who had lived at the complex for three years said he was on his way to work when police asked to take down some information from him.
He heard nothing before police arrived and said police activity at the apartment building was unusual.
