MI5 boss: Terror attacks will happen

London: Terrorist attacks cannot be completely prevented in a free society, the head of MI5 has said, as he warned a new pace of plotting and online technology meant attacks were being hatched in days.

Andrew Parker said Britain was now facing an intense threat from violent Islamist extremists who were devising plots at a tempo he had not seen before in his 34-year-career.

The director general of Britain’s Security Service made a rare public appearance to outline the severity of the threat after four jihadist attacks that have killed 36 people since March. A dramatic increase in the menace this year had seen attackers hatch plots in a matter of only days, he said. Parker also warned that internet firms were inadvertently helping terrorists conspire and they now had an ethical responsibility to help stop these worst excesses of criminal behaviour. He called on tech firms to help the Government tackle the “dark edges” of the online revolution, which was giving an advantage to violent extremists and enemy spies.

Parker said the “dramatic upshift” in Islamist threats in 2017 meant there “is more terrorist activity coming at us more quickly and it can be harder to detect”.

Speaking in central London, he said MI5 and the police had stopped 20 plots in the past four years, including seven since March, and would “continue to find and stop most attacks”.

But he warned they could not be expected to stop them all and it was likely more would follow. He said: “Attacks will occur sometimes because this is a free society, a liberal democracy, and we do not monitor everybody all the time and I wouldn’t wish to live in a country that was like that.”

“I think we have to be careful that we don’t find ourselves being held to some sort of perfect standard of 100 per cent, because that just isn’t achievable.”

Parker also said technology firms were inadvertently helping terrorists.

He said: “These threats are sometimes now coming at us more quickly, whether crude but lethal attack methods - for example using a knife or a vehicle - or more sophisticated plots when in today’s world terrorists can learn all that they need online to make explosives and build a bomb.

“Attacks can sometimes accelerate from inception through planning to action in just a handful of days. This pace, together with the way extremists can exploit safe spaces online, can make threats harder to detect and give us a smaller window to intervene.”