The number of Salafists in Germany has increased twofold since 2013, the interior ministry said Wednesday, surpassing December's "all-time high."

The number of individuals classified as Salafists by regional authorities in state offices for the Protection of the Constitution reached 11,000, the ministry said, confirming an earlier report from German newspaper Tagesspiegel.

Five years ago the German intelligence agency BfV placed this number at 5,500 — half of the current total.

Salafism is a fundamentalist Islamic ideology. Security authorities see Salafism as a potential entry point to Islamist terrorism.

Just under 5 million Muslims live in Germany, meaning that the current number of Salafists makes up roughly 0.22 percent of Germany's total Muslim population.

Read more: Islam researcher: Not all Salafists are the same

Fast growth in Berlin, Hamburg, eastern states

Security figures pointed out that while the rate of growth of the Salafist scene had slowed, "stagnation or even a reduction was not yet in sight," Tagesspiegel said.

Authorities fear that Salafism could be an entry point to Islamist terrorism

The sources also told the paper that the Salafist scene's fastest growth was taking place in Germany's smaller states, such as the city-states of Berlin and Hamburg.

Michael Kiefer, an expert on extremism at the Institute for Islamic Theology at the University of Osnabrück, told DW that he believed the number of Salafists in Germany would decrease due to "Islamic State" (IS) defeats in Iraq and Syria.

"IS was built on a propaganda model extolling the foundation of a caliphate. This project has collapsed," he said.

"When we assume that the activity of IS in 2013-14 worked to mobilize (radicals), then we can also say that the group's hard defeat will work to demobilize support," he said.

Adherence to Salafism in the former East German states has also grown, though the total numbers remain low. The Brandenburg Interior Ministry reported a current total of 100 Salafists in the state, an increase of 20 people from 2016.

In December, BfV President Hans-Georg Maassen said the number of Salafists living in Germany had reached an "all-time high" at 10,800. The intelligence agency highlighted recruitment of new individuals to the ideology through private spheres, including the internet, which makes it harder for authorities to monitor.

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