Standoff between Islamist preacher Sven Lau and German security agents shows the difficulty of drawing a clear line between opinion and sedition.
WUPPERTAL, Germany—Fundamentalist Islamic preacher Sven Lau claims he has a simple test to separate undercover officers from passersby. He gives them the finger. If they don’t respond, he said, “they’re intelligence agents.”
German authorities have spent at least eight years monitoring Mr. Lau, a 34-year-old ex-firefighter from a Catholic family who now practices a strict form of Islam known as Salafism.
Officials say Mr. Lau is one of the most prominent Islamic preachers in Germany, with a charismatic message that lures young Germans into radical Muslim circles. The head of Germany’s domestic intelligence agency called Mr. Lau one of the country’s “best-known propagandists.” Authorities allege Mr. Lau inspired some of his followers to join Islamic militants in Syria and Iraq, and fear they will eventually spawn terror attacks in Germany and the West.
Mr. Lau, who has delivered sermons to hundreds of listeners at town squares across Germany, denies the allegation. Despite wiretaps and searches of his home and computers by authorities, he remains free. He denied any ties to terrorism or the extremist group Islamic State—“I’m not pro-IS,” he said—and described his past trips to Syria as humanitarian work.
The standoff between Mr. Lau and German security agents illustrates the difficulty of drawing a clear line between opinion and sedition at a time when European authorities face growing numbers of disaffected Muslims, some of them taking on radical views. Security officials say they monitor a wide range of Islamist proselytizing but only a small minority pass the threshold for prosecution on charges of supporting terrorism.
German authorities, who say they still watch Mr. Lau, acknowledge he seems to have found a safety zone.
“He continues to radicalize young people and creates fertile soil for future violence,” said Burkhard Freier, the domestic intelligence chief in Mr. Lau’s home state of North-Rhine Westphalia. “To prove this under the rule of law with means that will stand up in court is, well, difficult.”