In a statement, a police spokesman said one person was before the Youth Court and inquiries were continuing, so they were unable to provide further information.
"Vigilante action will not be tolerated,'' the spokesman said.
"People need to be aware these actions also impact current and future police investigations targeting online offenders, and it could hinder or prevent a prosecution.
"We also discourage members of the public from taking matters into their own hands, as they could place themselves and members of the public at risk.''
Anyone with concerns about potential offending was encouraged to contact police immediately.
All complaints would be taken seriously, the spokesman said, and followed up as appropriate where there was criminal offending of that nature.
