BERLIN (AP) — Rescuers say a 52-year-old German explorer who was injured in a fall deep inside an Alpine cave is well enough for the evacuation process to begin.

Researcher Johann Westhauser has been stuck 1,000 meters (3,280 feet) underground since suffering head injuries in a rock fall Sunday inside the Riesending cave system near the town Berchtesgaden in southern Germany.

The head of the rescue operation says doctors have given the OK for Westhauser to be stretchered out, a difficult process that will take days because of the narrow shafts and vertical lifting involved.

Andreas Wolf said Thursday that some 30 rescuers from Germany, Austria, Italy and Switzerland are in the cave preparing the evacuation.

Westhauser was spelunking with two colleagues when the rock fall happened some 6,000 meters from the entrance.

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