One of Germany's most prominent Islamic extremists has been arrested on suspicion of supporting a foreign terror group.

Federal prosecutors said Sven Lau was arrested Tuesday in western Germany.

He is suspected of four counts of supporting the group Jaish al-Muhajireen wal-Ansar, or JAMWA, which was designated as a terrorist organization by the United States last year.

German prosecutors said in a statement Tuesday that the 35-year-old Lau was the go-to contact for extremists wanting to fight for JAMWA in Syria.

He is also suspected of providing financial and material support to the group.

Lau, a convert to Islam, made headlines last year when he attempted to establish a "Sharia police" in the city of Wuppertal to enforce a strict interpretation of Islam.