Terrorism is "no longer over there, it's here" according to a security expert.
Dr Sally Leivesley told Daybreak terrorists were frequently fighting abroad in countries like Syria and Afghanistan, "learning the trade" and then returning to England.
Dr Leivesley was speaking after the head of the MI5, Andrew Parker, went on a blistering attack against Edward Snowden and the Guardian for exposing America and Britain's mass-surveillance programme.
"It is quite interesting because he [Parker] talks about why we have to live without fear and it's why he..tries to dull down the statements that he is making, because he is really telling us we have to expect this.
"But he is also saying that it is so unpredictable that they can't tell if they are going to be successful against these attacks, because the whole of policing, is lifted off up the ground.
"It is no longer just the police on the street. It is really through the airwaves."
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