The new 'big issue' faced by the UK 20 years after deadly 7/7 terror attacks

Social media is now the likeliest way people could be radicalised, a security expert has warned, as the UK marks 20 years since the 7/7 bombings. Professor Anthony Glees said the way extremism is spread is considerably different to 2005, when four Islamist suicide bombers killed more than 50 people in London.

He believes that while mass attacks like 7/7 appear improbable, the war in Gaza could have a "huge radicalising impact", particularly on young Muslims. He said "extremist preachers" and recruitment networks aren't as prominent as they were 20 years ago, with lone wolf attacks a more likely threat. "Today, it is quite different - it is just people going onto social media," Professor Glees told the Express.

"MI5 has said it... all these things propel people towards the idea that only an act of terror can stop slaughter in Gaza in a way that simply didn't exist 20 years ago."

He added: "That is a really big issue, I think, that has to be dealt with head on and I don't think we are dealing with it head on."

The University of Buckingham lecturer described the cyber world as a "double-edged sword", explaining how it offers advantages and disadvantages to security chiefs.

The expert said while it "exponentially increases" the reach of material potentially designed to radicalise, it also gives British intelligence more surveillance - including messages and online activities.

"It's telling us that MI5 knows where to look and it knows whom to look for," he said.

"Those are key components, whereas 7/7 and in those years, they didn't really know where to look. They didn't know what kind of people might be inspired by terror - now they've got a much better idea."

The expert added: "I think we are better placed to identify and neutralise attacks."

On July 7, 2005, 52 people were killed and more than 770 were injured when four suicide bombers detonated devices on London's public transport system - three on Underground trains and one on a bus during rush hour.

The attackers, Mohammad Sidique Khan, 30, Shehzad Tanweer, 22, Hasib Hussain, 18, and Germaine Lindsay, 19, were British citizens.

It was the worst single terror attack on British soil in history.

Last year, MI5 Director General Sir Ken McCallum said since March 2017, the agency and police have together "disrupted 43 late-stage attack plots".

"The headline split of our counter terrorist work remains roughly 75% Islamist extremist, 25% extreme right-wing terrorism," he said.

Professor Glees said he believes there is a "very slim chance" of an attack similar to the 7/7 bombings happening again in the UK.

"I think we have learnt, and above all, our security community has learnt a great deal since 7/7," he said.

"This kind of carefully coordinated mass attack by an extremist Islamist network, I think would these days be detected at a much earlier stage.

"It looks to me, obviously from the outside, as if MI5 and the counter terrorism police are doing a very good job - not just in disrupting potential Islamist attacks."

He added: "They also know what to look for and they know where to look for it and that's really the big difference.

"What [Sir Ken] McCallum says very clearly is that what they're now seeing are kind of individual jihadist extremists. Individuals turning to terror who aren't part of a given network, who are not being choreographed by an individual [like] an Osama Bin Laden, but acting alone, although there is a kind of ideological commitment to Islamism."