Sensitive patient data that was stolen in a cyber attack has been published on the internet by what the company is calling "malicious actors".

Data from Pinnacle Midlands Health Network was hacked on the 28th of September and has over the weekend been released publicly online.

The stolen records cover more than 450,000 patients from Waikato, Lakes, Taranaki and Tairawhiti districts.

Chief executive Justin Butcher spoke to Māni Dunlop.