BERLIN (AP) — Germany’s mountain rescue service says it could complete the rescue of an injured cave researcher from the country’s deepest cave on Thursday or Friday as experts make good progress through the labyrinth’s passages and shafts.

Johann Westhauser suffered head injuries June 8 while nearly 1,000 meters (3,280 feet) underground in the Riesending cave system in the Alps near the Austrian border. Teams of rescue experts embarked last Friday to bring Westhauser, who is strapped to a stretcher, to the surface.

By Tuesday, they had raised him to about 500 meters (1,640 feet) below the ground.

Mountain rescue official Stefan Schneider told reporters the operation is on schedule.

He added: “Let’s wait and see whether the rescue we’re all eagerly awaiting comes off on Thursday or Friday.”

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