An emergency beacon has gone off a year after search teams recovered the bodies of its owners - an Australian couple who died while climbing in Aoraki/Mt Cook National Park, Fairfax reported.
A Department of Conservation mountain rescue team discovered the beacon had been activated where Stuart Jason Hollaway and his partner Dale Amanda Thistlethwaite died in December 2015.
The personal locator beacon's mysterious activation on Friday puzzled police. It had never gone off before.
Twizel Constable Les Andrew confirmed to Fairfax that the pair owned the beacon after police checked a list of their belongings and photos of the gear recovered from the mountain.
"It was below where the bodies were recovered," Andrew said.
Rescuers found Hollaway and Thistlethwaite's bodies on January 1 this year at the bottom of a steep eastern slope of Mt Silberhorn after they failed to make contact via radio.
They were both experienced climbers and authorities believed they died in a fall.
It was unusual timing that the beacon went off nearly 12 months after they died, Andrew said.
"It's close to the anniversary."
The mountain rescue team were unable to recover the beacon because it was unsafe to do so, instead they asked the Rescue Co-ordination Centre New Zealand to disable it.
Rescue Co-ordination Centre NZ senior search and rescue officer Ramon Davis told Fairfax water or rust may have set the beacon off.
Beacons could last a decade if they had good batteries, he said.
The signal would last 24 to 72 hours after activation, making it impossible for the beacon activated on Friday to have been activated last year.
"No way it could last a year."
Beacons have unique identifiers and their owner's emergency contact details are logged in a database.
Aoraki/Mt Cook DOC operations manager Mike Davies told Fairfax he was not familiar of the details of Friday's incident, calling it an "unusual" situation.
Crews initially thought the beacon had been removed from the site because its pouch was taken with the rest of the couple's gear, Andrew said.
Friday's activation served valuable learning opportunity for police.