Ex-MI5 chief warns against crackdown on encrypted messaging apps

Jonathan Evans says although encryption services have hampered terrorism fight he does not support curtailment of its use

A former head of MI5 has spoken out against curtailing use of encryption in messaging apps despite warning that Islamist terrorism will remain a threat for up to another 30 years.

Jonathan Evans said the terrorist threat to Britain was a "generational problem", and suggested the Westminster Bridge attack in March may have had an energising effect on extremists.