Estimates for UK-based terrorists are 'tip of iceberg'

MI5's figure of 23,000 "suspects of interest" who pose a potential terrorist threat is just "the tip of the iceberg", says a senior former intelligence adviser to the government.

In an interview with BBC Newsnight, Col Richard Kemp said the UK is "reaping the horrors" after years of failing to deal with extremism.

Col Kemp is former chair of the Cobra Intelligence Group which advises the government on intelligence matters and coordinates the work MI5 and MI6.