One person was detained on suspicion of attempted murder after shots were fired in the southern town of Reutlingen, near Stuttgart, German prosecutors said.

The searches follow raids in December, when German police foiled a plot by members of Germany's Reichsbuerger movement to stage a violent coup and install aristocrat Heinrich XIII Prinz Reuss as national leader.

Reichsbuerger (Citizens of the Reich) does not recognise modern-day Germany as a legitimate state.

"Federal prosecutors had 20 properties searched today. The measure is related to the Reichsbuerger scene. A policeman was shot," tweeted Justice Minister Marco Buschmann.

"This shows how dangerous the missions are. It is the duty of the authorities to disarm Reichsbuerger," he said.

The raids, in eight German states and in Switzerland, targeted five individuals suspected of belonging to a terrorist organisation and a further 14 people who were not suspects but may have possessed useful material, German prosecutors said.

The person believed to have been involved in the shooting was not originally one of the suspects.

No further arrests were made, said a spokesperson for the prosecutors.

Broadcaster ARD first reported the searches, saying the latest suspects were from southern Bavaria, northern Lower Saxony and eastern Saxony, and included police officers and soldiers. Some of them were believed to have formed other networks hostile to the state, it added.

(Reporting by Madeline Chambers; Editing by Friederike Heine, Miranda Murray and Bernadette Baum)