German author and undercover journalist Shams Ul-Haq claims to have visited hundreds of mosques across Germany, Austria, and Switzerland and says that one in ten mosques there preaches radical Islamic ideas.

Mr Ul-Haq, who is originally from Pakistan, said that the number of mosques that preach hatred of the west and adherence to radical Islamic ideas is growing across the German-speaking countries of Europe with at least 50 in Austria alone, Kronen Zeitung reports.

During his visits, Ul-Haq also noticed that the imams were often not the real drivers behind what was preached but were pushed by financial backers who dictate what they said in sermons.

Ul-Haq also met with radical Salafists but said that they did not immediately approach him and were very wary of newcomers.

“It took almost two years for some to get in touch with me. They felt their way slowly, examining, watching. They are not stupid,” he said.

Undercover Report: Islamic Radicalism Rife in ‘Hotbed of Terror’ Asylum Homes https://t.co/YnUjyabXaE pic.twitter.com/NcZmHWihZF — Breitbart London (@BreitbartLondon) December 6, 2016

“They do not immediately talk about jihad or Syria. They want you to realise that you want to react and do something yourself,” he added.

Notorious hate preachers like Sharia Police founder Sven Lau, who was convicted of attempting to aid terrorists last year, and Pierre Vogel, are popular among younger members of the mosques, according to Ul-Haq.

Propaganda videos of Vogel have been found in several cases of radical Islamic violence such as the 2016 attack on a police officer in Hanover by 15-year-old Safia S. who was revealed to have been inspired by Vogel’s videos.

Another major difference Ul-Haq noticed was that between mosques preaching in German and those preaching in Arabic with the 43-year-old saying far more radical ideas were preached in Arabic saying, “naked hatred is often spread in Arabic.”

The most radical mosque he claimed to have visited was the An-Nur Mosque in Winterthur, Switzerland, which has become notorious for radicalism and where an imam was arrested for promoting the murder of non-Muslims in 2016.