BERLIN (AP) — German federal prosecutors on Tuesday took over an investigation of anti-government extremists who allegedly planned to cause a long nationwide blackout and kidnap the country's health minister, saying there's evidence that the group constituted a terror organization.

Four German men were arrested on April 13 over their alleged roles in the plot, which authorities suspect was aimed at producing “conditions similar to civil war” and ultimately bringing down the government and parliamentary democracy.

Federal prosecutors, who in Germany handle terrorism and national security cases, said they were stepping in because there are sufficient indications that the suspects may have founded or been members of a terrorist organization. The men are also suspected of preparing a serious act of violence and violating weapons laws.

Investigators have said that the suspects were associated with the protest movement against coronavirus restrictions and with the Reich Citizens movement, which disputes the legitimacy of the post-World War II German constitution and, by extension, the current government.

Authorities said at the time of the arrests that the group’s declared aim was to destroy electricity supply facilities and cause a long blackout across the country as part of its goal of creating chaos. Police seized 22 firearms, including a Kalashnikov rifle, along with hundreds of rounds of ammunition, thousands of euros in cash, and numerous gold bars and silver coins. They also found forged COVID-19 vaccination and test certificates.

German Interior Minister Nancy Faeser said earlier this month that the investigation pointed to “a serious terrorist threat,” and that the plan to kidnap Health Minister Karl Lauterbach and fantasies about overthrowing democracy constitute “a new quality of threat.”