Police in the southern German state of Bavaria have detained a suspect during a hearth at Adolf Hitler’s Alpine mountain retreat, the Kehlsteinhaus, also identified as the Eagle’s Nest.

Dispatchers in Traunstein acquired a hearth alarm from the constructing at 21:15 native time (19:15 GMT) on Friday and firefighters discovered it engulfed in flames.

Difficult terrain was hindering efforts to extinguish the blaze and it was still burning early on Saturday, police said, with some 200 emergency personnel deployed. There were no reports of accidents.

The Nazi dictator used the retreat, which lies above the city of Berchtesgaden, as a part-time seat of authorities and met commanders there to plan the invasion of the USSR in 1941.

Hitler also used the space as a backdrop for propaganda movies portraying him as a lover of animals and nature.

A legal investigation is under method to decide whether the suspect is linked to the hearth.