German authorities have arrested four alleged members of a far-right group during an investigation into several extremist organisations.

The men, identified only as Leon R, Maximilian A, Eric K and Bastian A in line with local privacy rules, were detained in central Germany, prosecutors said.

They said the four were leading members of a far-right combat sports group, Knockout 51, which held training sessions in the eastern city of Eisenach and aimed to indoctrinate young men and train them in street fighting.

The group, which has links to far-right players in other parts of Germany, tried to set up a “Nazi neighbourhood” in Eisenach and its members injured several people, prosecutors said.

They also allegedly travelled to protests against coronavirus restrictions where there were clashes with police and counter-protesters.

In all, 61 properties in various parts of Germany were raided on Wednesday.

Prosecutors said they are also investigating 21 people suspected of keeping alive the Combat 18 Deutschland group despite a ban by German authorities.

They are investigating 10 people suspected of being members of or supporting an organisation called Atomwaffen Division Deutschland.

Prosecutors described it as a terrorist group and a German offshoot of Atomwaffen Division, a white supremacist organisation which has existed in the US since 2015.

Leon R is one of the suspects in that case.

And prosecutors said five people are under investigation in connection with SKD 1418, a far-right chat group active in 2019 and 2020.