Regional leaders of the far-right Alternative for Germany (AfD) voiced outrage Thursday after a fourth state branch was officially labeled a far-right extremist group.

The reaction came as authorities released on Thursday a redacted version of the 142-page assessment that classified the AfD's branch in Brandenburg, which surrounds Berlin, as a confirmed far-right extremist group.

Brandenburg's domestic intelligence chief, Wilfried Peters, said the party advocated for people who do not "belong to the German mainstream" to leave the country.

"This is about discrimination and exclusion," Peters said during the presentation of the 140-page report outlining the justifications for the classification.

"The AfD Brandenburg is highly xenophobic and, in parts, racist. The party advocates an ethnocultural concept of the German people that excludes and discriminates against certain individuals," he said, referring to the far-right party's discriminatory stance against immigrants and Muslims.