Here's the relevant section of 2000 Terrorism Act in the UK - the police appear to be just using text from that http://www.legislation.gov.uk/ukpga/2000/11/sec

Here's the relevant section of 2000 Terrorism Act in the UK - the police appear to be just using text from that http://www.legislation.gov.uk/ukpga/2000/11/section/1 http://www.legislation.gov.uk/ukpga/2000/11/section/1