London Bridge attackers were part of banned jihadi network

For years they were dismissed as hateful clowns, ultimately harmless - to be ignored rather than feared.

But now the banned al Muhajiroun network and its hate preacher Anjem Choudary are being linked to increasing numbers of violent extremists.

Sky News can reveal that two of the London Bridge killers, Khuram Butt and Rachid Redouane, were followers of the banned organisation.

That news comes as little surprise to those who have been following the activities of this radical network.

Although al Muhajiroun was banned by the UK government shortly after the 7/7 attacks in London, it continued to thrive and grow support, changing its name several times in attempts to avoid prosecution.

An analysis of all Islamist terror offences and attacks in the UK over almost two decades shows a quarter were committed by those with links to al Muhajiroun and its various incarnations.

Those plots include the murder of British soldier Lee Rigby by Muslim converts Michael Adebolajo and Michael Adebowale, who had both been followers of Choudary.

Another member of the group was Siddhartha Dhar, who skipped bail while under investigation over his association with Choudary.

He fled to Syria to fight with Islamic State. He is widely believed to have been the masked man who appeared in a horrific video in which Syrian prisoners were killed on camera.

Al Muhajiroun was founded by preacher Omar Bakri Mohammed, but when he fled the UK for Lebanon in 2005, Choudary took centre stage as the organisation's main spokesman.

According to police and intelligence services, in the years that followed, Choudary became the UK's most prolific jihadi recruiter.

Khuram Butt was drawn to the group under Bakri-Mohammed, but continued to follow Choudary when he took over.

Prominent anti-extremism campaigner Mohammed Shafiq, chief executive of the Ramadhan Foundation, said Butt called him a "Murtad" - traitor in Arabic - when he confronted Choudary outside parliament about comments he made in the aftermath of the murder of Lee Rigby.

Mr Shafiq said: "The police turned up and Anjem, Khuram Butt and two other men were escorted away towards Millbank and I stayed in College Green. I am not surprised that Khuram Butt carried out the terrorist attack and there are serious questions for the authorities."

Choudary managed to stay on the right side of the law, expertly blurring the lines between freedom of speech and criminality, for many years.

However, the law finally caught up with the hate preacher in August 2016. He was convicted of inviting support for ISIS and jailed for five-and-a-half years.

Security sources have told Sky News that Choudary is linked to more than 300 individuals, who have travelled to Syria and Iraq in recent years to join up with IS.

Although Choudary is behind bars, he leaves behind a legacy of radical links, of followers who've descended into violent extremism.

The preacher has never denied his links to those who've turned to terrorism. But he always maintained he should not be held responsible for the actions of others, of people he had no control over.