Police are putting extra officers on the streets of Cambridgeshire following the rise in the national security threat level to “critical”, meaning an attack is expected imminently.

Assistant Chief Constable Dan Vajzovic said: “The thoughts of everyone at Cambridgeshire Constabulary are with those who lost loved ones or have been affected by this terrorist incident.

“As has been reported in the media the threat level has moved to critical, meaning that an attack is expected imminently.

“However, I want to reassure people in Cambridgeshire that there is no specific threat relating to our county and that you can go about your business in safety.

“To provide you with that reassurance we will be increasing our patrols, particularly in city centres or at large events.

“We continue to monitor the situation nationally and locally and would ask the public to be our eyes and ears.”

Detective Superintendent Glen Channer, head of the Eastern Region Counter Terrorism Investigation Unit, said: “At this time we are asking you, the public, to remain alert but not alarmed.

“If you see anything that causes you concern, then let us know immediately. If you have suspicions about someone’s behaviour then please do call us.

“Please keep a look out for anything that seems out of place, unusual or doesn’t seem to fit in with day-to-day life.

“It may be nothing, but if you see or hear anything that could be terrorist-related trust your instinct and ACT by calling the confidential national police hotline on 0800 789321. In an emergency situation, call 999.”

• Advice for the public:

• Remain alert at home, work and when out and about, but do not be alarmed. Report suspicious activity to the police by calling or visiting the Anti-Terrorist Hotline on 0800 789 321 or gov.uk/ACT

• Report online terrorist and extremist material online by clicking on gov.uk/ACT

• If are caught up in a firearms or weapons attack Stay Safe by following the ‘RUN. HIDE. TELL’ advice: RUN, if you can; HIDE if you can’t run; TELL, when you can, the police what’s happening. Further advice is available at: http://www.npcc.police.uk/NPCCBusinessAreas/WeaponAttacksStaySafe.aspx.