The advice is aimed principally at businesses and staff in organisations with responsibility for the safety of others.

It has been compiled by the Security Service's National Security Advice Centre, which works to protect Key Government assets and businesses vital to the UK's critical national infrastructure.

Anyone with information they think may help protect national security will be able to contact the Service directly via a secure page on the website in a section called "How You Can Help".

Security Awareness:

• Remind your staff to be vigilant at work and when travelling to and from the workplace
• Remind staff not to leave personal possessions or other items unattended as this can cause unnecessary security alerts
• Encourage staff to immediately report suspicions to their line manager
• Encourage staff to challenge unknown visitors or unusual behaviour. Is access to your premises controlled? Are passes issued to visitors/contractors?
• Are your premises covered by CCTV. Is it working correctly? Are the images properly recorded and stored?
  

Business Continuity:

• Review Business Continuity plans
• Have you a robust telephone/e-mail cascade system for contacting staff out of hours?
• Is essential data/records stored off site? Can IT systems be accessed remotely, if required?
• Have you robust banking and financial arrangements in place in order that payments can still be made and your business sustained?