The witness said he also saw a slug gun retrieved from the car, which appeared to be a white ute.
A 20-year-old man was taken to hospital from the address. Police confirmed a firearm had been presented, but the injuries received by the victim were not as a result of a firearm being used.
Police said the people involved in the incident were in custody, and three people had been charged with intent to cause grievous bodily harm.
A St John representative said, while a neighbour had heard a loud noise and thought it was a slug gun, they did not treat anyone with a slug pellet or gun shot injury.
They did treat a 20-year-old man with minor head injuries sustained from a physical assault, who was taken to Hawke's Bay hospital with a suspected concussion and multiple bruises.
Last night, a hospital spokeswoman said the man remained in a stable condition.
A resident said he first realised something was wrong when a police car pulled up in front of his house, and a police officer with a rifle entered the nearby property.
There was usually a lot of "ruckus" coming from the house involved, another resident said, and she often heard lots of yelling, swearing, and things being smashed at the property.
Police were talking to all parties involved, and said no further information was available at this stage.