MI5 warns of 'mass casualty attacks' against west

As dramatic events surrounding the terrorist attack at the offices of Charlie Hebdo magazine in Paris continue to unfold, Andrew Parker, director general of the Security Service, said transport networks and iconic landmarks were among western targets of "complex and ambitious plots" by Syria-based extremists.

Aviation bomb plots and Mumbai-style shootings in crowded places are thought to be among plans being developed by the shadowy group, which has Britain among its sights.

It is also understood the organisation in question is the so-called "Khorasan" cell, which is made up of veteran jihadists sent to Syria by al Qaida leader Ayman al-Zawahiri.

Khorasan is embedded within al Qaida's Syrian branch al-Nusra Front, which is known to include radicalised Britons who have travelled to the war-torn country to fight.

Addressing about 70 members of the Royal United Services Institute (RUSI) at MI5 headquarters Thames House yesterday, Mr Parker said: "We still face more complex and ambitious plots that follow the now sadly well-established approach of al Qaida and its imitators - attempts to cause large scale loss of life, often by attacking transport systems or iconic targets.

"We know, for example, that a group of core al Qaida terrorists in Syria is planning mass casualty attacks against the West."

He added: "Al Qaida continues to provide a focus for extremists to plot terrorist attacks against the West.

"British Islamist extremists still travel to South Asia, the Arabian Peninsula and other theatres to try to obtain terrorist training."

Khorasan has been described as a small group made up of around 50 fighters, including expert bomb makers and high-ranking members of al Qaida who moved to Pakistan following the 2001 invasion of Afghanistan.

US officials said they had been sent to Syria not to fight the government of president Bashar Assad but to "develop external attacks, construct and test improvised explosive devices and recruit Westerners to conduct operations".

In September, US military forces carried out air strikes against Khorasan after intelligence reports suggested that the group was in the final stages of plans to launch major attacks against Western targets including the United States.

Mr Parker said around 600 extremists are now among many Britons who have travelled to Syria - higher than previous estimates of 500.

The Director General said a significant proportion has joined Islamic State, the extremist group that has taken over large swathes of Iraq and Syria and is behind a series of beheadings of hostages in recent months.

"Despite its medieval tactics, Isil is a terrorist phenomenon of the modern age," he said.

"It makes full use of the modern social media and communications methods through which many of us now live our lives.

"By these means it spreads its message of hate directly into homes across the UK - both to those seeking it and those who may be susceptible to its distortion and glamorisation of horrific acts."

The Director General disclosed that in recent months three UK terrorist plots which would have led to deaths have been foiled by MI5 and its intelligence partners at MI6 and GCHQ.

It is understood the plots were a mix of mass casualty attacks and lone-wolf style killings as seen on the streets of Woolwich when Fusilier Lee Rigby was killed in 2013.

Outside Iraq and Syria, the Security Service believes that since October 2013 there have been more than 20 terrorist plots either directed or provoked by extremist groups in Syria.

Among them were the deaths of four people shot in Brussels last May by a French returnee from Syria, while in Canada, a soldier was killed in a hit and run attack and another shot dead outside the parliament building.

Other attacks have been foiled, Mr Parker said, such as in early 2014 when police in France seized improvised explosive devices from a flat linked to another Syria returnee.

"But we cannot be complacent," he said. "Although we and our partners try our utmost we know that we cannot hope to stop everything."

The Director General said the UK threat level, ramped up to severe from substantial in August, meaning an attack is highly likely, is unlikely to abate for some time.

Mr Parker also argued the case for improving intelligence agencies' capabilities to access terrorist communications.

He said his "sharpest concern" as head of MI5 is the "growing gap between the increasingly challenging threat and the decreasing availability of capabilities to address it".

His comments come after a report by the Intelligence Security Committee into the death of Fusilier Rigby criticised social networking giant Facebook for failing to flag extremist communications made by one of the soldier's killers.

It is understood security officials want to see increased co-operation from internet firms, as well as increased powers to demand access to communications when they do not comply.

"The dark places from where those who wish us harm can plot and plan are increasing. We need to be able to access communications and obtain relevant data on those people when we have good reason to do so," the Director General said.

Sir Malcolm Rifkind, who chairs the Intelligence and Security Committee (ISC), said the Paris attack gave "added weight" to the case for intelligence services being given stronger powers to intercept communications.

It had become "increasingly difficult" to access vital evidence, he told BBC Radio 4's Today.

"What is emerging in Paris is that the two individuals responsible for the terrible massacre at Charlie Hebdo may have been linked to al Qaida in the Yemen.

"They must have been communicating with people in the Yemen over the last few days, the last few weeks.

"The hugely important objective is to enable intelligence agencies in Britain and France and other democracies to be able to get hold of these communications to try and prevent incidents of this kind.

"I think it gives added weight to the point that in a realistic world, if you are dealing with international terrorism, how do international terrorists communicate with each other? In the modern world they communicate through the internet, through email, through social messaging and all the technical ways that we are aware of.

"So our intelligence agencies, acting under law, acting on good reasonable grounds, with authority, have to have the power to intercept particularly international communications that might be relevant."

Chancellor George Osborne insisted that the security services had the resources they needed because protecting the country was "the national priority".

He told BBC Breakfast: "We have put a huge amount of planning and effort, from the police, from the security services, from the Government, into anticipating what might happen, stopping some of these attacks.

"Of course we have been successful in doing that over the last year.

"Within the last few weeks we have put extra money - over £100 million - into specifically monitoring people who are going to conflicts in Syria and Iraq, these self-starting terrorists who get their ideas off the internet and then want to perpetrate horrendous crimes.

"So we are putting a huge effort in, as the director general of MI5 has said over the last 24 hours, that is the threat we face and we face the threat from a more complex plot.

"So we have got to be vigilant, we have got to have the resources there.

"My commitment is very clear: this is the national priority, we will put the resources in, whatever the security services need they will get because they do a heroic job on our behalf."

Anthony Glees, director of the Centre for Security and Intelligence Studies at the University of Buckingham, said he did not believe a Charlie Hebdo-style attack would happen in the UK but warned that killings such as the murder of soldier Lee Rigby could be repeated.

"Could somebody in the UK get an AK47 assault rifle, could they get the ammunition and could they plan a military style operation without MI5 getting wind of it? I very much doubt it," he said.

"Could we have another Drummer Lee Rigby attack of butchery? Yes we could, but we can do a lot to prevent that too, by doubling the resources available to MI5.

"In all these cases that we know about, we're dealing with people who have come across the radar of the security community, but the security community has decided that given the resources it has, they are desirable targets but not essential targets."

He added: "If we had more people working in this field we could have more people looked at as essential targets, and I think that is the call that now has to be made."

Mr Glees said the British security services have successfully monitored electronic communications over the past 10 years to combat terrorism.

"I think the past decade has shown a very good record of success. I do not think that the sort of things that are happening in France could happen in the UK. Not because there aren't the same kind of Islamists, but because we in the UK have taken a different attitude.

"The British people are perfectly prepared to give our security community access to electronically-stored data in order to keep us safe. There's no doubt about that. That's not the case in France," he said.

RUSI director-general Professor Michael Clarke said that greater public vigilance was crucial to combating terrorism in the UK as attacks have occurred around the world.

"There has been a wave building out there for the last two years and it's now beginning to break in Canada, Australia, Belgium, France and we are in the firing line just as much as anyone else," he said.

"Greater vigilance on the part of the public is the thing that now needs to be stepped up again.

"The public has become quite relaxed over the past four or five years because the threat hasn't seemed so great.

"What's now required is that the intelligence services and the police need to keep on doing what they have been doing fairly successfully, but greater protection will now all depend on greater public vigilance and that comes in a thousand different ways.

"All you can do is - without alarming people - just create the atmosphere that everyone goes about their business quite normally but is just a bit more careful in reporting anything they see that might give the police some useful leads."