UK counter-terrorism: Public help essential - police chief

Metropolitan Police Assistant Commissioner Mark Rowley, who is in charge of counter-terrorism at the Association of Chief Police Officers, has said the help of communities, families, business and other agencies is essential in combating the threat of terrorism in the UK.

His comments came at the start of a week-long police initiative, involving more than 3,000 officers, intended to remind the public how they can help fight terrorism.

The UK's terror threat level was raised from "substantial" to "severe" earlier this year in response to conflicts in Iraq and Syria.