BERLIN (AP) — Rescuers have begun the difficult process of bringing to the surface a 52-year-old German explorer who was injured in a fall deep inside an Alpine cave.

Johann Westhauser suffered head injuries 1,000 meters (3,280 feet) underground Sunday while exploring the Riesending cave system near the town of Berchtesgaden, close to the Austrian border.

Doctors had to climb 4 kilometers (2.5 kilometers) into the cave to reach Westhauser and make sure he was well enough to be brought out.

Westhauser will be strapped to a stretcher for much of the way out but in certain narrow passages he will have to assist rescuers.

Officials said Friday it will take up a week to bring Westhauser to the surface.

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