Official figures on the arrests made in Britain under the 2000 Terrorism Act over the last 12 months were released by the Home Office on Thursday, December 7.
Anthony Glees, a Professor of Politics at the University of Buckingham and director of its Centre for Security and Intelligence Studies, said the increase was "definitely not for show."
The surge in arrests can be attributed to more people reporting to the police, or better intelligence-led policing, he explained, noting:
"I suspect we need to listen to what the Director General of MI5 said a few weeks ago — that this was happening at a 'scale and pace we've not seen before', a tempo unique in his 34 years in MI5," Dr. Glees told Sputnik.
'A Year Like No Other'
Home Secretary Amber Rudd said recently "2017 has been a year like no other" in terms of terrorist attacks.
In March a man drove a van at pedestrians on Westminster Bridge in central London, climbed out and then stabbed a police officer to death outside the Houses of Parliament before being shot by police.
In May 22 people were killed at an Ariana Grande concert in Manchester by a suicide bomber and then in June three men in a van drove into revelers on London Bridge and began stabbing people in the Borough Market area before being gunned down by police marksmen. In September a bomb went off on a Tube train at Parsons Green in west London, injuring several people.
According to the latest figures from the Home Office, of the 400 who were arrested only 115 were charged, 18 of which were for non-terrorist offenses.
It was the biggest number of arrests since terrorist-related offenses began to be recorded separately in 2001, the year of 9/11.
"There have been 23 terror plots since 2013 but we are told 20 have also been disrupted, seven since the Westminster attack," Professor Glees told Sputnik.
Professor Glees said 69 of the 78 terrorist trials in the past year had led to convictions, a 16 percent increase on the previous year.
"What that says to me is that thanks to good intelligence-led policing, arrests happen only when there is operational evidence that can be used to convict, and convict is what it does," he told Sputnik.
Twelve people were arrested in connection with the Westminster Bridge attack, 23 for the Manchester Arena attack and 21 for the Borough Market attacks, although all six actual perpetrators were killed.
Home Office security minister, Ben Wallace, said he did not believe the threat was a "short-term spike."
But Professor Glees said Brexit was in fact another threat, on the basis the UK would be forced to leave Europol, the Europe-wide police organization.
"If ever there was a worse time for the UK to turn its back on Europol, it'd be hard to imagine it. Some of the UK media said [EU negotiator Michel] Barnier had accused the UK of walking away from the EU-wide fight against terror and the EU was 'kicking the UK out of Europol'. That's quite untrue," he told Sputnik.
The intelligence agencies know of 23,000 potential jihadists, of whom 3,000 are suspects, and 500 investigations are live at present in Britian, said Dr. Glees.
"The problem for MI5 is knowing who is a priority target and sometimes those who are not priority targets may get picked up. Counter-terrorism policing is a deadly serious activity in the UK, and they don't arrest people just to be seen to be doing something," Professor Glees told Sputnik.
According to the data, Britain has seen a huge increase has been recorded in the number of white, non-Asian (77 percent) and female arrestees.
"More women have been arrested because more are turning to violent extremism… We've seen the empowerment of women in our society, but since the days of the Suffragettes and Rosa Luxemburg women have shown they can be every bit as radical," he told Sputnik.