While the circumstances and suspected motivations behind the Finsbury Park incident are yet to be made clear, it comes amid mounting concern over far-right extremism in the UK.Warnings that the threat could be growing were raised after the conviction of Thomas Mair for the murder of Labour MP Jo Cox last year.The Government’s Prevent and Channel programmes, which work to intervene before individuals are drawn into violent extremism, have seen a rise in the number of referrals linked to far-right ideology.Counter-terrorism police have said that, while the threat is not of the same gravity as that posed by Islamic State or al Qaida, there are extreme right-wing groups attempting to provoke violence and sow discord. Muslim leaders as well as politicians have called for greater security at mosques following the Finsbury Park attack, in which a man drove a vehicle into worshippers exiting a mosque.One man died and 10 others were injured when a van was rammed into worshippers in a terror attack near a London mosque, before the driver is said to have screamed: “I’m going to kill all Muslims”.The van driver – described by witnesses as a large white man – was detained by members of the public after the incident in Finsbury Park early on Monday that police said had “all the hallmarks of terrorism”. This attack follows warnings of an unprecedented anti-Muslim backlash after recent terrorist atrocities.Police in London recorded a spike in the number of Islamophobic incidents in the wake of the London Bridge outrage earlier this month, with 20 recorded on June 6 – compared with a daily average of 3.5.It was the highest daily tally for 2017, and also higher than the numbers registered after the Paris attacks in November 2015, and the murder of Lee Rigby in May 2013.In a speech last week, a former police chief warned that anti-Muslim sentiment online has been “relentless” following the London Bridge attack on June 3. Secretary general of the Muslim Council of Britain Harun Khan said: “During the night, ordinary British citizens were set upon while they were going about their lives, completing their night worship.”My prayers are with the victims and their families. It appears from eyewitness accounts that the perpetrator was motivated by Islamophobia.”Over the past weeks and months, Muslims have endured many incidents of Islamophobia, and this is the most violent manifestation to date.”Given we are approaching the end of the month of Ramadan and the celebration of Eid with many Muslims going to local mosques, we expect the authorities to increase security outside mosques as a matter of urgency.”Labour’s shadow home secretary Diane Abbott, whose Hackney North and Stoke Newington constituency lies close to the scene, called for police to review security at mosques. She tweeted: “Terror attack outside Finsbury Park mosque. Police must urgently review security for all mosques”London Mayor Sadiq Khan said mosque security would be ramped up: “Given we are approaching the end of the month of Ramadan and the celebration of Eid with many Muslims going to local mosques, we expect the authorities to increase security outside mosques as a matter of urgency.”Some have said they are scared to go back to worship, worrying copycat attacks could occur and that they are a “target” for terror. The sceneCredit:Reuters/James Cropper Far right extremism is growing problem. My local mosque hires private security just so we can pray due to recent arson attacks #FinsburyPark— Ikrām (@Supersporadic_) June 19, 2017 Figures on terror-related arrests have shown an increasing number of white suspects are being held.In the year to the end of March, there were 113 arrests of white people, compared with 68 in the year before – an increase of 66%.The white ethnic group accounted for 37% of all terrorism-related arrests in the 12 months, compared with 26% in the previous year.Statistics on individuals’ ethnicity are not broken down by type of suspected extremism.Dr Alan Mendoza, executive director of the Henry Jackson Society think tank, said: “Coming a year after the murder of Jo Cox, we have witnessed what appears to be another hateful act in the community. “It is looking increasingly likely that this is the latest example of a growing threat of far-right extremism in the UK.”The Government must ensure urgently the security services have all the resources they need to investigate and prevent extremism-inspired attacks of whatever origin.” A Suspect is arrested at the scene of a Terror attack in Finsbury ParkCredit:Sky News Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings. Mak Chishty, an ex-Metropolitan Police commander who had been the country’s most senior Muslim officer before his retirement, said: “The backlash has been something of a different scale.” Witnesses of the terror attack at Finsbury Park Mosque have vowed to return for prayers tonight despite being scared and shaken after the incident.Saide Ottman, 27, was leaving the mosque at the time of the attack, and told The Independent: “I heard people screaming and at first I thought it was an accident or a fight had broken out. Then I saw about 10 people holding a man back,” he said. “People told me he had clapped after the attack and seemed proud of what he’d done, and said ‘yes, I did it’.”“This is racism. I haven’t ever experienced racism in London before, this is the first time. I’m scared, we’re all scared, but I’m going back to the mosque tonight.” I just texted my Muslim neighbors to please be safe at their mosque. They have security, but they need the police. #Nabra #FinsburyPark— Noel (@Frogerta) June 19, 2017 “There were discussions with the police. A lot of people were shocked.”There is a lot of fear at the moment. But it’s not the first time. We have had a fire bomb in the mosque, someone tries to leave a bomb, I don’t know if it was a hoax.”The EDL have tried to attack us, a few years back.”We are a target. I am worried to go back there. This could inspire other attacks against our mosque.” Huseyin Ali, 32, a caretaker at the charity Mind, who lives in Finsbury Park, said: “I came about an hour afterwards. There was a lot of confusion. People were just trying to find out what was happening.