After the gang members were restrained by people from the crowd a third person on the back of the ute fired four to five shotgun rounds in the air and into the crowd.
"It was a miracle no one was hurt,'' Mr McCarthy said.
Mr McCarthy said it was another cowardly gang shooting in Wairoa.
"Enough is enough,'' he said.
"The community needs to stand up and assist police... the number of gang shootings in Wairoa is becoming ridiculous and it is only a matter of time before an innocent bystander is injured or killed.''
The white Nissan ute was found at a house in Wairoa and police were making good progress in their inquiry, but have appealed to the public for more information.
As of this afternoon no arrests had been made, police spokeswoman Kris McGehan said.
Last October a Mongrel Mob member was shot through the window of his vehicle by a Black Power member at the Mobil service station in Wairoa.
Police recently arrested and charged a man over the shooting.
- NZPA