The Muslim population of Britain surpassed 3.5 million in 2016 to become around 5.5% of the overall population of 64 million, according to figures extrapolated from a recent study on the growth of the Muslim population in Europe.
In real terms, Britain has the third-largest Muslim population in the European Union, after France, then Germany.
The growth of Britain’s Muslim population can be attributed to immigration, high birth rates and conversions to Islam.
Analytical data released by the British authorities show that until February 2017 approximately 850 people from the UK have travelled to support or fight for jihadist organisations in Syria and Iraq.
About half have since returned to the UK.
More than 100 people have been convicted so far of offences relating to the conflict.
Some of the individuals travelled to the region.
Others tried to travel but were stopped.
Finally, there is a group of people who have been convicted of offences relating to assisting the first two categories.
A further 600 British citizens have been caught trying to enter Syria to join the so-called Islamic State and other extremist groups, the former foreign secretary Philip Hammond has said.
Half of Britain’s jihadists are now radicalised online: Proportion being brainwashed via the internet doubles in just five years.
Report author Hannah Stuart, senior research fellow at the security think-tank, said: ‘Online radicalisation is increasing – the prevalence of the internet as a medium for engagement with extremism more than doubled.
‘First Al Qaeda and now Islamic State are ahead of the game in terms of using the internet and social media for propaganda.
Islamic State is now increasingly using the power of the internet to target people. It is now much easier to find extremist material.’
In August last year, MPs on the Commons’ Home Affairs Select Committee said forums, message boards and social media platforms were the ‘lifeblood’ of Islamic State and other terror groups.
Extremists used networks such as Google, YouTube and Facebook as the ’vehicle of choice in spreading propaganda’ to recruit terrorists – yet the companies did too little to tackle those glorifying violence, they said.
The scale of the problem was drummed home when it was revealed that social media firms had refused to remove hate preacher Anjem Choudary’s poisonous online rants that urged Britons to carry out atrocities before he was jailed.
Those who had been identified by the security services had halved from 61 per cent before 2011 to 29 per cent afterwards.
This suggested a growing challenge for spies because a growing proportion were so-called ‘clean skins’.
Only 10 per cent of terror attacks were carried out by ‘lone wolves’ unconnected to wider extremist networks. And 1 in 10 terrorists had watched a beheading video – pushing them to even greater depravity.
The report said the increase in plots involving knives makes tackling the problem harder for the security services than when terror cells plotted bomb strikes.
That is harder now with knife attacks, compared with when groups were spending months acquiring bomb-making equipment. That is a big difference.’
Link between Birmingham and Jihadis
Members of Birmingham’s Muslim communities acknowledged the linkage between their city and Islamist extremism, which many attribute to poverty and drug abuse that make youths vulnerable to jihadist recruiters who operate like gangs.
But Muslims in Birmingham also deeply resent what they see as a grossly unfair reputation, countering that most residents are proud and law-abiding.
Many also see their neighborhoods as reassuring refuges from the backlash of anti-Islam bigotry roiling Europe and elsewhere.
The bigotry has often focused on Birmingham.
A few years ago, a Fox News terrorism commentator had to apologize for describing Birmingham as a “Muslim-only city” where non-Muslims “don’t go.”
Nonetheless, Birmingham, Britain’s second-biggest city behind London, has produced a disproportionate number of convicted Islamist militants, including some linked to the Sept. 11 attacks, and to last year’s bombings in Brussels.
So many Islamist militants have been born in Birmingham — or have passed through — that the Birmingham Mail newspaper once lamented that the city had the dubious distinction of “Terror Central.”
“The extremist schools of thought seem to have become more embedded in Birmingham than in other parts of the country,” said Nazir Afzal, the former chief crown prosecutor for northwest England, who is from Birmingham.
Mr. Masood, who converted to Islam in his late 30s, was born and raised in an affluent village in southeast England.
He spent much of his adulthood in and around London, interrupted by jail time and two yearlong relocations to Saudi Arabia. But Birmingham was his last residence.
Birmingham was the birthplace of Britain’s first suicide bomber, the residence of a financier of the Sept. 11 attacks, and the place where Al Qaeda hatched a plot to blow up a commercial airliner in 2006.
When a masked member of the Shabab, the Somali extremist group, celebrated the murder of the soldier Lee Rigby in a 2013 video, he listed Birmingham as the first source of its fighters.
The man who is believed to have recruited the militant known as Jihadi John, the Islamic State executioner with the King’s English accent, was from Birmingham, as was his closest associate.
Other prominent militants who have come through the city’s underground networks include Abdelhamid Abaaoud, organizer of the 2015 Paris attacks, and Mohamed Abrini, a Belgian national who helped plot the 2016 Brussels attacks.
In 2014, Birmingham was at the center of a so-called Trojan Horse plot in which, it was alleged, a group of Islamist extremists had sought to infiltrate and take over two dozen state schools.
A recent report by the Henry Jackson Society, a politically conservative research organization, found that one in 10 convicted Islamist militants in Britain come from five Birmingham neighborhoods.
David Videcette, a former senior counterterrorism official, said that Birmingham had a better established extremist network than London — a city of seven million — which helped to explain why, in his view, many investigations lead “back to Birmingham.”
Part of Birmingham’s allure to prospective militants is its diverse sprawl of Muslim neighborhoods where they can blend in easily, local activists said.
“It’s a hiding place or a passing place to do what they want to do, and keep a low profile,” said Mohammed Ashfaq, director of Kikit, a community organization that helps young people who are drawn to drugs and extremist ideology.
If a militant were to hide, for example, in Birmingham’s Muslim neighborhood of Sparkbrook, Mr. Ashfaq said, “no one looks at them twice.”

Birmingham is also much poorer than London, providing a more exploitable population for extremists, Mr. Ashfaq said, recalling how his organization dissuaded two youngsters from joining the Islamic State. Both were drug addicts.
“A lot of kids are on drugs, or from single-parent families, or who experience domestic violence,” Mr. Ashfaq said.
In the neighborhoods of Sparkbrook, Washwood Heath and Alum Rock, where many of Birmingham’s Muslims live, mosques dot the cityscape, some offering Shariah councils for family matters.
After-school madrassas serve a growing demand for parents who want their children to study the Quran.
Even state-funded schools often accommodate religious demands, allowing for lunchtime prayer, shortened days during Ramadan and optional head scarfs.
To many outsiders, the segregation is striking. But Muslim residents, particularly women, speak of their neighborhoods as safe havens from an increasingly hostile society.
“There is safety in numbers,” said Sara Begum, 20, shopping on Coventry Road, a bustling area where eateries advertise halal meat from Kashmir and Syrian cuisine. Ms. Begum, who wears a face-covering niqab, rarely leaves her neighborhood for fear of being insulted or worse. She said a friend’s head scarf had been ripped away by far-right youths near Birmingham’s downtown train station.
“I feel safe around here because a lot of other women dress like I do,” she said. “Other people look at this neighborhood, they see a lot of brown people and a lot of Muslims and they worry about security.”
Within hours of last week’s attack, Muslim women in Birmingham received text messages warning about the far-right English Defense League mobilizing, and urged them to stay inside after dark.
Small Heath Park, where girls in head scarves play soccer and men in Muslim garb huddle to share a picnic, feels like a different world than the city center, a 10-minute drive away.
There are recently arrived Somalis, third-generation Bangladeshis and European converts, like Alicia Fierens, who moved here with her Chinese husband, also a convert, six years ago because Belgium had become too anti-Muslim, she said.
“We were having our first child and we didn’t want him to grow up with that,” she said. Birmingham is friendlier, “as long as you stay in the area.”