Last year , a terrorist plot on the UK was foiled " in the final hours before the planned attack " after terrorists used interception technology to monitor phones of people linked to the plot , the Chief Reviewer of Terrorism intelligence said as it detailed examples of how the freedom it was granted under the so - called " king 's charter " have benefited the UK . GCHQ also provided support to both MI5 and European intelligence and helped to build up 1,600 international leads , in the forms of email addresses , phone numbers and other identifiers , shortly after the Paris attacks .
Last year, a terrorist plot on the UK was foiled "in the final hours before the planned attack" after GCHQ used interception warrants to monitor phones of people linked to the plot, the Independent Reviewer of Terrorism Legislation said as it detailed examples of how the powers it was granted under the so-called "snooper's charter" have benefited the UK. GCHQ also provided support to both MI5 and European partners and helped to follow up 1,600 international leads, in the forms of email addresses, phone numbers and other identifiers, shortly after the Paris attacks.