The National Counter Terrorism Policing unit has released a video warning people what to do in the event of a terrorist firearms attack.
The release comes just over a month after 132 people were killed suicide bombings and mass shootings at cafés, restaurants and the Bataclan Theatre in Paris.
The four minute film, Stay Safe: Firearms and Weapons Attack sets out three key steps for keeping safe which are to “run, hide and tell”
The video shows office workers in a tower block as they flee from a gunman or gunmen.
The unit’s deputy assistant commissioner, Neil Basu, said: “The public should not be alarmed by this step.
“While the general level of threat to the UK is SEVERE, the probability of being caught up in a firearms or weapons attack is very, very small. However, it is important the public know what to do in the event of getting caught up in such an incident.
“Our advice has already been issued to tens of thousands of people during police-led security training sessions but it is only responsible that we issues this public safety guidance more widely.
“We know that from case studies and the testimony of people who have survived attacks that the advice given in the film has saved lives.
“With the threat level remaining at a high level, the police and security service continue to operate at a heightened state of readiness - we are working on hundreds of investigations and making an arrest a day.
“However, it is only with the ongoing support of communities that we can defeat terrorism - you are our eyes and ears so please be alert, but not alarmed.”
Anyone with information should call the Anti-Terrorist Hotline on 0800 789 321 or in an emergency, 999.