Labour Minister Simon Bridges says prosecutions are "very likely" for forestry owners who have breached safety standards.
Up to 150 forestry businesses have been inspected by officials to check their compliance with health and safety rules, and 14 have been shut down.
Mr Bridges told reporters this morning: "My understanding is that there is one prosecution pending, there are other investigations ... What I certainly can say is there is the likelihood of prosecutions in this industry."
He added: "We are warning the industry that they need to get their house in order. We're stepping up, we're resourcing this, doing the inspections, changing the law. We need them to take that seriously and also step up. Because if they don't, there will be consequences."
The Ministry of Business, Innovation and Employment was handling the prosecution but would soon hand it over to Worksafe New Zealand, a newly formed regulatory body.