A Swiss tourist suffered a suspected broken arm when she tried to dodge a boulder dislodged above her on the upper slopes of Mt Ngauruhoe this morning.
Taupo's Greenlea Rescue Helicopter was called after the 27-year old Swiss woman was hit by the large rock.
The woman was descending the mountain when a climber above her dislodged the boulder which came careering toward her.
She managed to duck the main force of the rock but as she tried to protect herself suffered a suspected compound fracture to her arm and a cut to her head.
The boulder was described by a witness as a monster.