Police in the US state of Nebraska are seeking more information about a man registered there as sex offender who is now in New Zealand.
Guy Verschuur, 51, and two woman were rescued from Kahurangi National Park in Golden Bay last month after they failed to return from a tramp.
After police released the names of those missing it was discovered that Mr Verschuur was listed on the Nebraska Sex Offender Registry for a conviction of false imprisonment of a minor in 1998.
Nebraska State Patrol investigator Charlie O'Callaghan has told Radio New Zealand News that Mr Verschuur left the United States without permission.
Mr O'Callaghan says he will be making a criminal case against him for leaving the country without notification.
New Zealand police say they have not been contacted for information or assistance.
Immigration New Zealand said last week that having reviewed his residency application from 2008, they should have required a character waiver given the type of crime of which he was convicted.
An immigration lawyer, John McBride, says a person could be issued a deportation notice if their visa was granted due to an administrative error.