A suspicious item has been blown up by the Defence Force near Aotea Square in Auckland.
A police spokeswoman said the area, which was cordoned off by police earlier tonight, was now safe and cordons would be lifted shortly.
She said people were asked to leave the area, including shops that were open late, but everyone would be allowed back into the area soon.
"I can confirm that the item has been made safe," she said. "We enlisted the NZ Defence Force, as is routine."
A passerby, Lucas Arthur, said the explosion seemed to come from around Aotea Square just before 7.40pm.
"It wouldn't be a loud detonation," he said. "I'm not an expert on bombs, but it was really loud. It seemed to echo throughout the city."
Earlier, police said an item of concern had been located on Queen St in central Auckland, at the intersection with Wakefield St.
Police are in the area to assess the item, and cordons are being established around this location for both motorists and pedestrians.
People are advised to avoid the area and comply with all directions from police staff.