Save Animals From Exploitation (SAFE) has registered its "disgust" at the behaviour it says was dished out to critics at last weekend's the Mid Northern rodeo in Whangārei.
Anti-rodeo activists had staged a peaceful protest outside the event, head of campaigns Marianne Macdonald said, while others bought tickets so they could video animal abuse. Both groups had been met with aggressive, bullying behaviour.
The behaviour of supporters said a lot about the culture of rodeo, she added.
The Mid Northern rodeo, in particular, has a history of illegal treatment of animals, and without video footage captured by activists the public will never know when animals are abused or killed.
"Vigilantes in the crowd took it upon themselves to confront, in the most appalling way, people who were peacefully filming," Ms Macdonald said.
"Rodeo organisers deny that they bully animals, yet the spectators believe they can take it upon themselves to physically assault others in attendance, just like the cowboys' assault animals in the rodeo arena."
The Mid Northern rodeo had in the past received a warning from the Ministry for Primary Industries for breaching animal welfare law, and legal action was also proceeding against an animal handler at the same event for alleged illegal use of an electric prod on calves.
"Filming and cameras have been banned at many rodeo events," she added.
"The organisers claim that that content can be taken out of context and used to show rodeo in a bad light. However, they can't get away from the fact that the context is rodeo, and the content is animal abuse.
"Just last week we learned that a second animal had been killed at the Gisborne rodeo, a fact that the Rodeo Cowboys' Association kept very quiet, even after the public learned that a bull had been killed.
"The Mid Northern rodeo, in particular, has a history of illegal treatment of animals, and without video footage captured by activists the public will never know when animals are abused or killed.
"The public has had enough of the disgraceful display of human dominance over animals at rodeos. It is urgent that the government steps in and bans rodeo cruelty immediately."
Meanwhile the organisers were disappointed with the weekend's crowd, the smallest in recent years, and the actions of some protesters who they said did not heed warnings not to film with high-definition cameras.
Police confirmed they had been called to the grounds on Saturday, but no arrests had been made. Most of the protesters stood at the main gates with message placards.
Mid Northern Rodeo member Dianna Bradshaw said no animals had been injured over the two days, but club president Noel Upton ended up in Whangarei Hospital with six broken ribs after his supposedly well-mannered mount bucked unexpectedly as he was helping clear the main arena of bulls.