An Opotiki councillor says there have already been acts of retribution after a street brawl and the death of a man on Sunday night, which locals say is gang-related.
Police are appealing for calm in the eastern Bay of Plenty town and have put extra officers on the streets.
Police were called to a large fight in Goring Street about 7pm on Sunday, and a few minutes later a man was found collapsed in nearby King Street.
Joe Collier was taken to Whakatane Hospital in critical condition, but the 21-year-old died soon afterwards.
The area commander for eastern Bay of Plenty, Inspector Kevin Taylor, said on Monday the death is causing tension in the town.
"A lot of people know other people, and it's clear that the incident last night has caused some tensions in the town. More of rumour of threats and retaliation - obviously, we don't want to see that happen."
But Opotiki District Councillor Barry Howe told Radio New Zealand's Checkpoint programme there's already been one drive-by shooting on Monday and a house has had all its windows smashed.
"One of the girls that used to work for me drove past when it happened and she came in the shop and told us. Pretty scary, she reckoned - really scary. It's whanau fighting whanau here in Opotiki because we've only got a small population."
Mr Howe says no one was hurt.
Although police can't confirm the shooting, they said they did receive a report of a possible gunshot heard at lunchtime.
Te Owai Gemmell, the chairperson of the Maori Wardens in Opotiki, said two groups from one family wearing different colours are involved. She said she has concerns for families who live close to where the incidents occurred.