- German authorities say those arrested are suspected of planning attacks on mosques and Salafist Muslims
- The four German nationals are accused of forming an extremist right-wing terror group
Authorities say the four -- three men and one woman -- are all German nationals and had formed an extremist right-wing terror group called the "OldSchool Society."
Authorities say they also uncovered explosives during searches of the suspects' homes and other properties.
The four suspects will go before an investigating judge on Wednesday.
They are named by the federal prosecutor's office as Andreas H., age 56, and Markus W., age 39, which two are suspected of being the group's leaders, as well as 22-year-old Denise Vanessa G. and 47-year-old Olaf O.
About 250 officers were involved in the nationwide search and arrest operation.