Some 200 police officers raided 13 homes in Berlin and elsewhere in Germany Tuesday, in connection with the arrests last week of two suspected members of an Islamic terror cell.
Police spokesman Michael Gassen said the raids were mostly on close associates of the pair.
"We were looking for further evidence in connection with last week's arrests," Gassen said, adding that the people targeted Tuesday were not accused of any wrongdoing themselves. Most were members of the same mosque in Berlin's Moabit neighborhood as the two suspects.
Last week's raids were part of a monthslong investigation into a small group of Turkish extremists based in Berlin.
Police on Friday arrested the group's leader, identified only as 41-year-old Ismet D. in accordance with privacy laws, who is accused of recruiting largely Turkish and Russian nationals to fight against "infidels" in Syria. They also arrested Emin F., 43, who is accused of being in charge of finances.
Authorities said there's no evidence the group was planning attacks inside Germany, but that it procured funding to help send fighters to Syria, as well as military materials like night-vision equipment.
They said the arrests were unrelated to the recent attacks in Paris or raids in Belgium.