'Isil is planning aeroplane attack on scale of 9/11,' warns US official
Isil and other terrorist groups are planning to target aircraft as they aim to carry out another major attack on the scale of 9/11, a top US security official has said.
Elaine Duke, acting US Homeland Security Secretary, said the groups were using smaller attacks to raise money and "keep their members engaged".
"The threat is still severe," she said in London after meeting UK Home Secretary Amber Rudd.
"The terrorist organisations, be it [Isil] or al-Qa'ida or others, want to have the big explosion like they did on 9/11.
''They want to take down aircraft, the intelligence is clear on that."
Europe has seen a string of crude attacks in the past year.
"In the interim they need to keep their finances flowing and they need to keep their visibility high and they need to keep their members engaged, so they are using small plots and they are happy to have small plots," Ms Duke said.
"Creating terror is their goal. A bladed weapon attack causes terror and continues to disrupt the world but that does not mean they have given up on a major aviation plot."
Ms Duke said the US and the UK would push social media firms at a meeting of G7 interior ministers this week to do more to tackle online militant material.
She said there had already been a change in the attitude of tech companies since a rally organised by white supremacists in Charlottesville, Virginia, in August turned deadly when a counter protester was killed by a car driven into a crowd.
"There has been a shift for us somewhat with the Charlottesville incident," she said.
"There are a lot of social pressures and they want to do business so they really have to balance between keeping their user agreements and giving law enforcement what they need.
"The fact they are meeting with us at G7 is a positive sign. I think they're seeing the evidence of it being real and not just hyperbole."
After a series of Islamist militant attacks this year, British Prime Minister Theresa May and her cabinet have been demanding action from tech leaders like Facebook, Google and Twitter to do more about extremist material on their sites.
British politicians have also called for access to encrypted messaging services like Facebook's WhatsApp, a campaign that US Deputy Attorney General Rod Rosenstein gave his backing to after meeting Ms Rudd and the head of the UK domestic spy agency MI5 last week.
Internet companies say they want to help governments remove extremist or criminal material but say they have to balance the demands of security with civil liberties.
"We would like to have the ability to get encrypted data with the right legal processes," said Ms Duke.