The manager of a trust that supports leavers from the Gloriavale religious community hopes the latest enquiry could be a tipping point for change.
The community near Greymouth has been the subject of previous investigations by police, Oranga Tamariki and the Charities Commission.
Police confirmed enquiries were ongoing in relation to a report they recently received, and staff from Oranga Tamariki had been on site over recent days.
Liz Gregory of the Gloriavale Leavers Support Trust said they were always hopeful for change.
"Every now and then there's an incident and they think 'this is it, this is gonna be the catalyst', and then it all just goes away.
"So we're looking on with real interest - is this all gonna go away in the next few years? That is a real possibility.
"They have done this for 50 years."
The trust was established last year to help people who decide to leave the religious community.
Some of those who have left have described Gloriavale as controlling, fearful, and oppressive. The majority are not allowed contact with people from outside the community.
Neither police nor Oranga Tamariki would confirm the nature of the enquiry.