Police commander for the Ruapehu area, Inspector Steve Mastrovich, said a group of about 10 international visitors was recently advised by tourism experts in Taupo and Turangi that they weren't equipped or experienced enough to do the crossing but carried on anyway.
"They drove to the track by private vehicle where they ignored further warnings by two TACTAG members not to proceed.
"They became lost and were very lucky to be rescued without mishap. These visitors need to understand that Search & Rescue isn't a back-up to poor decision making, and they need to listen to the advice of the people who have local knowledge."
Tongariro Alpine Crossing is recognised as one of the best day walks in the world and a lot of work has been done by TACTAG since its formation in 2007 to strengthen protocols that guide operators on weather conditions and the minimum equipment for trampers.
At TACTAG's latest meeting, the Department of Conservation said in the future it would require operators holding concessions to provide guiding and transport services for the crossing to be TACTAG members and abide by its protocols.