The investments of dozens of racing clubs are the subject of a joint investigation between the Serious Fraud Office and Internal Affairs over alleged pokie grant manipulations.
Late last month, both agencies executed search warrants and seized computers as part of the investigation.
At least three pokie trusts - the New Zealand Community Trust, Bluegrass Trust and Infinity Foundation - are being investigated, inquiries also focusing on thoroughbred and harness racing clubs across the country.
Racing Minister Nathan Guy said the investigation was an operational matter for Internal Affairs.
This week investigators continued to interview Otago and Southland racing club presidents, several of them confirming the nature of those inquiries.
Apart from inquiries concerning pokie grant applications, there had also been questions about investments by the clubs which promised large returns.
Investigations were not limited to the South, and about 75 people were expected to be interviewed nationwide.
Both the Serious Fraud Office and Internal Affairs declined to confirm details of the investigation, but issued the following statement last month.
''The Department of Internal Affairs has responsibility to ensure the integrity of the grants system in pokie machine gambling,'' Internal Affairs gambling compliance director Debbie Despard said.
''The wider community is disadvantaged if one group can gain preferential access to grant funding from gambling proceeds,'' she said.
