Munich prosecutors said that 16 properties in various parts of the country were searched as they sought incriminating publications and other evidence. They included the apartments of the suspects.
They said the group originated in the southern town of Neu-Ulm, at the Multi-Kultur-Haus - an Islamic center that Bavarian authorities shut in December 2005, charging that it threatened the coexistence of Germans and foreigners as well as security in the country.
A statement from prosecutors said the suspects' aim was "to Islamicize and radicalize Muslims and non-Muslims - particularly Germans who have converted to Islam." It added that they were suspected of trying to encourage those people's "readiness for Jihadist activities at home and abroad. The suspects were accused of using radical literature, audio and video material, Islam seminars and Internet discussion forums.