Germany's commissioner for immigration, refugees and integration is calling on mosques across the country to be more pro-active when it comes to preventing extremism among Muslim youths.

Aydan Ozoguz said in an interview Thursday with the daily Heilbronner Stimme: "We need to hold mosques more responsible when it comes to prevention among teenagers."

Ozoguz' call against Muslim extremism came after four violent attacks that shook the country recently.

Two of them were the first in Germany claimed by the extremist Islamic State group. The attackers were asylum-seekers who hadn't grown up in Germany.

On Wednesday night, police raided a mosque believed to be a "hot spot" for Islamic extremists in the city of Hildesheim. The raid didn't appear to be connected to the recent attacks.