Polish authorities have claimed it is unclear why at least eleven protesters slaughtered a sheep, stripped naked and chained themselves to the gate of Auschwitz.

The incident took place beneath the main gate, which bears the infamous slogan “Arbeit Macht Frei” (“Work sets you free”).

A BBC report originally cited Polish media saying the action was in protest against the conflict in Ukraine, but the motive remains unclear.

The bizarre actions of the group and the chosen location could indicate a more sinister motive, possibly an occult-related ritual.

In a statement, the Auschwitz museum said: “Using the symbol of Auschwitz for any kind of manifestations or happenings is outrageous and unacceptable. It is disrespectful to the memory of all the victims of the German Nazi Auschwitz concentration and extermination camp”.

About 1.1 million people, including one million Jews, were murdered by the Nazis at the camp.