Rescuers said Tuesday they aim to extract a researcher trapped with a serious injury in Germany's deepest and longest cave by the end of the week.
The Bavarian mountain search and rescue service said a Swiss team expected to reach the 52-year-old cave explorer, who is lying injured at a depth of around 1,000 metres (3,280 feet), later Tuesday.
He is to be gradually lifted back to daylight by way of five bivouac stations that are being set up in the Alpine cave Riesending on the Austrian border over the next three to five days, German news agency DPA reported.
The researcher was exploring the cave with two other people early Sunday when he suffered head and chest injuries from falling rocks.
A 42-year-old member of the expedition climbed out of the cave on his own to get help and it took a team of four first responders 12 hours to reach the stricken man Monday.
A team building the bivouac stations set up a telephone line at a depth of 400 metres to facilitate the operation.
A total of around 200 helpers have deployed from across the region to assist in the operation.
"The conditions are extremely narrow, the rescue won't be easy," doctor Christoph Specht told rolling news channel NTV.
"There are only a few people in Germany who know how to handle such a rescue."
The labyrinth-like Riesending cave, which has only been explored by researchers since 2002, is more than 19 kilometres long and up to 1,148 metres deep.
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