According to the National Counter Terrorism Security Office, victims of a terrorist attack like the Paris shootings should attempt to run away from the scene first, as long as doing so would not expose them to greater danger.
They should also insist others leave with them, and make sure belongings are left behind.
If running isn’t a possibility, the next option should be to hide from attackers and find cover from gunfire – instead of lying down in full view.
However, the NaCTSO guidance warns bullets can go through brick, glass, wood and metal, meaning it is safest to hide behind heavily reinforced walls.
Victims are advised to remain quiet, silence their phone, be aware of their exits and, if they are in an enclosed space, lock or barricade the door before moving away from it.
The refreshed guidelines, which can be viewed online, come as security is heightened across Europe in the wake of the assault on the French capital last week.
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