German Chancellor Angela Merkel. Photo: Reuters / Fabrizio Bensch.

German authorities raided the homes of four alleged neo-Nazis whom they suspect of attempting to obtain weapons, ammunition and explosives with which to attack political opponents, prosecutors said on Tuesday.

The raids, targeting a group calling itself the Northern Eagle, took place on Tuesday morning at locations in northern Germany.

Authorities have become increasingly concerned about the activities of far-right movements such as the Reichsbuerger (Citizens of the Reich), who do not recognize modern Germany as a legitimate state and insist the former “Deutsche Reich” is still alive despite Nazi Germany’s defeat in World War Two.

The domestic intelligence service estimates that the Reichsbuerger have several thousand members. One of them shot dead a police officer in Bavaria in October.

The home in eastern Germany of a fifth individual, who was not a suspect, was also searched. The timing of any possible planned attack was not yet known. No arrests had yet been made as part of the investigation, which continues.