Police say they were called to an address on Viaduct Harbour Avenue shortly after 9am today.
They say there were no reported injuries. Armed police are at the scene.
A friend of a Sofitel worker says a gunman entered the lobby firing.
A man who works near the Sofitel says he witnessed a man being arrested by at least eight police officers.
And a guest who was staying at the hotel told RNZ they heard two loud bangs.
The guest was staying for two nights and said he was sitting in the hotel restaurant when he heard the bangs.