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A jailed British hate preacher who has become ISIS’ rock star radicalizer in the U.K. has been linked to one of the suspected jihadis behind Saturday’s van and knife attack in London -- but it’s only the latest example of the Islamist leader’s tentacles touching ISIS plots in England.

Anjem Choudary, 50, was sentenced to 5 ½ years in prison in September for his vocal support of ISIS and had been a visible Islamist activist in England since at least 2002. He has called the 9/11 hijackers “magnificent martyrs,” declined to condemn terror attacks on British soil and predicted Britain will become a Muslim country within 30 years.

He’s also been – at least – an inspiration for several of the terror attacks that have plagued England in recent months.

CLICK HERE TO VIEW DOCUMENTARY INCLUDING FOOTAGE OF LONDON TERRORIST

“If you look at jihad as a skill, Choudary is very good at it,” said Ryan Mauro, Shillman Fellow for the anti-Islamist Clarion Project. “He is as likeable as you can be and still be a jihadist.”

Though police haven’t released the names of any member of the trio involved in the weekend’s ISIS-claimed attack, multiple media outlets have reported one of the suspects was featured in a year-old British television documentary, "Jihadis Next Door." In the film, the man is seen praying near an ISIS flag with Mohammed Shamsuddin, an associate of Choudary.

“Anyone who is seen praying with one of Choudary’s close associates should be assumed to be a radical, because his circle isn’t large,” Mauro told Fox News. “His message is, his few supporters shows how devout he is.”

Khalid Masood, who killed four people in London in March during a van and knife attack, showed an interest in Choudary’s teachings and his group, al Muhajiroun, The Times of London reported.

“He cites Islamic scripture left and right, so he’s very good at answering tough questions in a way that doesn’t sound mean-hearted or crazy, so it’s as appealing a way to present violent jihad as you can get,” Mauro said. “He’s also very good at promoting groups like ISIS without giving you the one-sentence soundbite that allows you to incriminate him.”

Salman Abedi, who blew himself up outside an Ariana Grande concert in Manchester last month, was reportedly controlled by the same ISIS cell responsible for the November 2015 Paris attacks – an assault Choudary once praised as “inevitable.”

Even from his current perch behind bars, the charismatic Choudary remains a dangerous influence in Britain, Mauro said.

“Whenever there is a jihadist attack in the U.K., if you were going to ask me to place a bet if they were a fan of his content, I would bet ‘yes,’” Mauro said.

“His influence is here to stay, even if he were to die tomorrow.”