Rescue workers recovered the victim late Saturday evening, a spokeswoman from Oberpfalz police in Bavaria said.

Four experienced cave explorers were in the Muehlbachquellhoehle cave system in the Franconian Jura, she said.

Some 700 metres from the entrance “there was an accident, and it is not yet clear what the exact cause was,” she said.

Another member of the group turned back and alerted emergency services around 4 pm (1500 GMT).

Emergency services had earlier attempted to bring the injured person to the surface. The fire service, water rescue, ambulance service and police were all at the scene.

Ultimately they were only able to recover the body.

The details of what happened were not immediately clear.

“The assumption is currently that it was an accident,” the police spokeswoman said.

A police investigation should give more information.

The Muehlbachquellhoehle is one of the longest known cave systems in Germany. It is partially filled with water.

A rescue operation in 2014 brought cave exploration in Germany into the public eye.

A cave explorer was hit in the head with a rock in the deepest cave in Germany, the Riesending cave, also in Bavaria and close to the Austrian border.

He suffered a traumatic brain injury and was brought back up from a depth of 1,000 metres in a rescue operation that lasted 11 days, used the help of some 700 people and cost almost one million euros.