A shot fired in a gang brawl in Taradale's CBD, on Sunday, struck the rear of a child's car seat, while the child was in it.
The pellet from a shotgun was fired when rival gangs, Mongrel Mob and Black Power, clashed on Sunday about 1pm. Between 30 and 40 people were thought to have been involved in the brawl.
A 25-year-old man received injuries to his head, face and torso from a single gunshot.
He remains in a serious but stable condition at Hawke's Bay Hospital.
"Fortunately the child was unharmed, but this behaviour is completely unacceptable and we are determined to hold those responsible to account," said Detective Inspector Rob Jones.
"Tensions between the Mongrel Mob and Black Power have continued to escalate in recent months with Police investigating a number of serious incidents and outbreaks of violence in public places – many of which have been witnessed by members of the public," Jones said.