KEY POINTS:
A teenager zapped by a Taser as he apparently tried to be a peacemaker in a fight is facing a range of weapons and assault charges after allegedly attacking a man with a metal bar and lashing out at police.
The 17-year-old was caught on video being Tasered as up to four policemen held him on the ground.
One witness said police got the "wrong man" and were heavy-handed.
But other witnesses have told the Herald the youth hit a man with a metal bar several times before police arrived on the scene in Henderson, Waitakere City, on Thursday.
"When the policeman got there he began lashing out, punching and kicking the officer and being an absolute menace," said Melissa Church, who was in her car when the fight broke out in front of her.
"I was absolutely disgusted to hear he was being made out to be an innocent who was trying to help."
Luke Shalfoon caught the incident on his cellphone video camera about 2pm at the intersection of Great North Rd, Ratanui St and Railside Ave.
He said on Thursday the police had no reason to Taser the teenager.
Last night, Mr Shalfoon stood by his version of events, saying four officers had pinned the youth to the ground and the Taser wasn't necessary.
Ms Church, who had her 1-year-old baby and her mother in the car, said the people shouting out that police "had the wrong guy" were themselves involved in the brawl.
Many more people were applauding the police and telling them they had the right man, she said.
Another witness, Rebecca Ellis, said she would give a statement to police today and agreed the Tasered man was "nowhere near innocent".
"It took four police to restrain him and the officers got a bum rap. It was a very violent situation and they did a fantastic job."
Two other witnesses have backed that version of events.
The youth was in custody last night and will appear in Waitakere District Court on Monday.
Inspector Scott Webb said police were still trying to find out what sparked the brawl, which it is understood involved at least six people.
A second man had been arrested and would face weapons and assault charges. Police were hunting for more people, including a woman who fled the scene in a car, driving directly at an officer who tried to stop her.
An investigation into the use of the Taser was under way, Mr Webb said, but police were "absolutely convinced" it was justified.
"The men had knives, screwdrivers and metal bars and some of those involved were known to police."