Jihadis are sending up to 100,000 Twitter messages a day to plot terrorism , Europe ’ s police chief has warned . In a chilling account of how IS is exploiting technology , Rob Wainwright , the director of Europol and ex-MI5 officer , urged social media firms to help authorities stem the terrorist threat , saying that encrypted communications were the ‘ most significant challenge ’ to tackling terrorism . IS is known to use encrypted tweets to recruit fighters and ‘ jihadi brides ’ , including the three British girls who fled to Syria earlier this year . Scroll down for video . Rob Wainwright , the director of Europol , urged social media firms to help authorities stem the terrorist threat . Saying that IS has 50,000 Twitter accounts , Mr Wainwright told a BBC radio investigation : ‘ We ’ ve built our counter-terrorist capability in recent years very much on the basis of being able to monitor their communications . 'As the communications of terrorist networks and criminal groups have moved increasingly [ online ] , it ’ s opened up a whole new wave of problems for us even in the open internet , let alone the Darknet. ’ His comments follow a report last year into the murder of Fusilier Lee Rigby , which found that Facebook had failed to pass on information that could have prevented his death . The full interview will be broadcast today at 11am on BBC Radio 5 live . Aqsa Mahmood , who fled to Syria from Glasgow , is said to have used Twitter to encourage terrorism .
Rob Wainwright , the director of Europol , says social media a huge problem . He told BBC Radio 5 live that there are many ways to use it for criminal purposes and