RNZ has approached police for comment.
The volunteers said she believed that the assaults were motivated by the young people’s desire to show off on social media.
She also observed that some students were targeted by the offenders for their designer shoes, clothes and phones.
Many of the incidents had centred around the transport hub and the main town centre adjacent to that, she said.
Last Friday, schools warned students to avoid the New Lynn transport hub over fears of a planned mass brawl between students.
This week, police are investigating another assault in New Lynn on Monday afternoon - one of a series of youth violence incidents around the transport hub in recent weeks.
Police said the incident was reported around 1.30pm and those involved had left the area on foot.
Meanwhile, videos have also been circulating on social media, showing a group of teenagers kicking a young person at the New Lynn McDonald’s, and another video shows a group of teens assaulting a person in Green Bay.
A McDonald’s spokesperson said it was aware of the video, and that they were in ongoing talks with the New Lynn Business Association and the police to address the ongoing problem.
Police said they were aware of the recent incidents in New Lynn and Green Bay, and that the videos were of a “concerning nature”.
There was increased police and security presence in New Lynn last week, including around the transport hub, they said.
Police said they would continue to have a visible presence in the area, especially before and after the school day.
Meanwhile, Auckland Transport said it had deployed a Western Line roaming officer for every day of the week.
The officer moved to the New Lynn station after 4.30pm every day, and stayed there until late night, AT said.
AT said it had been meeting regularly with police and local elected members to discuss measures to tackle the current safety concerns.
- RNZ