Far North police have been contacted by at least 35 people, many of them overseas travellers who have long since returned home, following last week's arrest of Main Street Lodge owner Michael Harris.
Harris is due back in court on Thursday on 39 charges relating to young men staying at his lodge. It is alleged he drugged backpackers, indecently assaulted them and took intimate photos.
Police believe there are at least 16 victims aged between 18 and 26 from various countries including the UK and America, but mostly from Germany. All were thought to be longer-term guests staying in the lodge owner's residence.
A special 0800 number and email address have been set up, leading to a number of calls from possible victims.
Police searched the lodge after a complaint by a male tourist early last week. It is believed that images found on a computer led to the other charges.
Harris, 56, bought the lodge in 2011 for a reported $1.2 million and spent $200,000 upgrading it. His arrest has shocked Kaitaia's business and tourism community.
The UK-born businessman is thought to have previously run hostels on the Gold Coast and in the UK, but police say Kaitaia is the current focus of their investigations.
Detective Sergeant Rhys Johnston, of Far North police, said three more potential victims from Germany had been identified since news of Harris' arrest broke.
He urged anyone making contact with police to give their full name and as many contact details as possible, including landline and cellphone numbers, email and Skype addresses.
He also asked potential victims to provide a photo of themselves to help the inquiry team. All information would be kept confidential.
"It's very important for us to speak to anybody who has stayed in the owner's residence over the last two-and-a-half years. These victims are unlikely to know that something has happened to them, although they may have suspicions."
Mr Johnston praised the man who came forward last week for his courage.
"It's as reflection of the trust and confidence in the Kaitaia police that they're willing to come forward, and that we'll do something about it," he said.
The lodge remains open but a tourism and arts expo scheduled to take place over the weekend was cancelled.
Call 0800 SNAP01 (0800 762 701) or email operationsnap@police.govt.nz with any information.