In a bid to clamp down on domestic terror networks, Scotland Yard arrested nine people, including a radical Islamist preacher, in London on Thursday morning on charges of being members of banned organizations and supporting terrorism, according to media reports.

Anjem Choudary -- a self-styled preacher and former head of banned Islamist group Islam4UK -- is reportedly among the nine people arrested. Choudary, who claims to be an expert in Shariah law, has, over the years, gained notoriety for making inflammatory statements calling for implementation of Shariah, or Islamic law, throughout the United Kingdom. The arrests were reportedly made when officers of Scotland Yard’s Counter Terrorism Command carried out raids on 18 different locations across London.

“These arrests and searches are part of an ongoing investigation into Islamist related terrorism and are not in response to any immediate public safety risk,” Scotland Yard said, according to a report by The Guardian.

Choudary also expressed his support for the Islamic State group, the Sunni extremist group that now controls territories in northern Syria and Iraq, reportedly calling its leader Abu Bakr al-Baghdadi as “the caliph of all Muslims and the prince of the believers.”

The arrested men, ranging in age from 22 to 51, are being held for questioning at police stations in central London.