Police have given private details of up to 10,000 TradeMe users to prison inmates.
Police obtained the information belonging to traders on the country's biggest auction website during their nationwide investigations relating to the so-called terror raids last year, the New Zealand Herald reported.
The information – 24,000 pages in 16 boxes - was passed to defence lawyers and in one case to Jamie Lockett, currently in prison as one of 16 arrested on firearms charges.
One of the boxes contained details such as names, user names, email addresses, phone numbers and home addresses of up to 10,000 Trade Me users.
TradeMe told the Herald it was served with a search warrant with which it had to comply.