Queenstown police say Swedish backpacker Christoffer Tornberg (23) - reported missing two weeks ago from Queenstown - is an illegal overstayer who is probably trying to avoid Immigration New Zealand.
Detective Grant Miller, of Queenstown, said police were no longer concerned for the former Queenstown supermarket worker's wellbeing after it was confirmed on Monday three sightings in the Queenstown area were "100%" genuine.
"He obviously doesn't want to be found.
We don't believe anything untoward has happened to him and we think his disappearance is related to his immigration status and he's now unlawfully in the country," Det Miller said.
Before the confirmed sightings Mr Tornberg was last seen on October 6 - just a week after his working holiday visa expired.
Det Miller said Mr Tornberg will not face charges of wasting police time.
A spokesman for Immigration New Zealand (INZ) said he could not comment on individual immigration cases without a privacy waiver.
However, he said people who overstayed their permit remained here unlawfully and had 42 days from the date they became unlawful to appeal possible removal to the independent Removal Review Authority.
During those 42 days they cannot be thrown out of the country.
"If they are in New Zealand unlawfully they can choose to leave voluntarily at any time before a removal order is served and not face a ban from returning - although the fact that they overstayed may be taken into account in considering future applications," he said.
If they do not appeal by the end of the 42-day period, Immigration New Zealand may serve a removal order.
Depending on the circumstances - for example, if INZ believes an overstayer could go into hiding - they may initially be held in custody by police for up to three days.
"If for any reason they can't be removed from the country during this time, INZ must apply for a warrant of commitment in order for them to continue to be held in custody.
"A judge can also permit their release subject to conditions such as where they live, and reporting requirements."
Before deportation, INZ conducts a humanitarian interview to ensure the removal is appropriate given their circumstances.
People who are deported are automatically banned from returning for five years, and to return must fulfil certain criteria.
