They are also accused of arson, unconstitutional sabotage and disruption of public services, German media report.
A far-left group has claimed responsibility for the arson attack on cable lines in the city that left 45,000 households and 2,200 businesses without power. Around 25,500 households and 1,200 businesses have still not had their electricity restored, Die Zeit reports.
On Thursday, authorities expect power to be restored for all affected customers.
