Eyewitnesses report seeing shotguns and machetes used in a large fight in Stokes Valley, Lower Hutt this afternoon.
Social media users said the fight took place on George St near Delany Park and gunshots were heard by members of the public nearby.
Police are searching nearby houses in an attempt to locate individuals involved.
A police spokesperson said armed police were also in attendance as a precaution and cordons had also been put in place.
One woman said the fight took place near the intersection of Speedy St, on the road and in a park.
"Huge group fighting in the park and over the road. Shotguns and machetes. Quiet now but still wouldn't risk it," the woman wrote.
Another woman told Newstalk ZB she saw about a dozen gang members fighting and heard "bangs" but didn't see any firearms.
However, the woman did see some gang members armed with machetes during the incident.
"We heard some yelling, we thought it was a sports event so we went outside and there was about 10-15 mongrel mob members in the park," she said.
"They were yelling at a group of people ... it was quite aggressive then we heard some bangs and some cars took off."
The woman said lots of people had walked out onto the street to watch the fight unfold.
Last year there were two gang-related shootings on Hanson Grove, Stokes Valley.
In early October, a man was shot during a drive-by shooting.
In early December, a 39-year-old man was shot on the same street and was taken to hospital with non-life threatening injuries.
Police first received calls about gunfire at 11.56pm before they received multiple calls about more gunshots going off in the valley.
"They were really aggressive ... it's not the first time this has happened, we've got young children so it feels like a really unsafe neighbourhood," the woman said.
A police spokeswoman said police were responding to a disorder incident in Stokes Valley.
"Police are responding to a disorder incident in Stokes Valley. Police were called about 3.45pm. No further information is available at this stage," she said.
Members of the public are asked to avoid the area as police work to understand the circumstances around the incident.