A New Zealand hostel owner accused of drugging and sexually assaulting several young male tourists that he hosted was arrested this week after two German travelers reported him to police.

After searching his business, the Mainstreet Lodge in Kaitaia, police arrested 56-year-old Mike Harris on 39 charges of indecent assault, aggravated wounding and making intimate visual recordings.

According to police, Mr. Harris filmed his assaults and recorded himself molesting at least 16 male victims over two and a half years, mostly overseas tourists from 18-25, who were drugged so heavily that they may not even be aware of the assault.

“These victims are unlikely to know that something has happened to them, although they may have suspicions,” Detective Senior Sergeant Rhys Johnston told TVNZ.

Police believe Harris assaulted far more than the 16 men in the tapes they recovered, and noted that more than 30 more potential victims have come forward in the day since they made details of the case public. All were backpackers passing through town, including tourists from Germany, England, Scotland, and the U.S.

“It is very important for us to speak to anybody who has stayed in the owner’s residence over the last two and a half years,” Johnston added. “Callers are concerned about whether something has happened to them and we want to be able to provide these potential victims with the right support as well as gather the evidence necessary.”

Harris will appear in Kaitaia District Court next Thursday, when the number of charges against him is expected to rise.

Anyone who fears they may have been a victim of Mike Harris is being asked to email the New Zealand police at [email protected]