‘Terror threat is the highest I’ve ever seen,’ says MI5 chief

Britain faces an unprecedented terror threat from Islamic State and Al Qaeda fanatics plotting ‘mass casualty’ attacks over the internet, the head of MI5 warned last night.

In a rare public speech, Andrew Parker said the Security Service thwarted six UK terror attacks in the past year and several overseas.

But he warned: ‘We can never be confident of stopping everything.’

The director-general of MI5 said the threat from jihadis was on a scale he had never seen in his 32-year career.

And he warned there was now a ‘greater ambition’ among terrorists to carry out mass casualty attacks in Britain as the threat showed ‘no sign of abating’.

‘It may not yet have reached the high water mark,’ he said.