WATCH: What you should do during a terrorist attack

This police video gives instructions on how to stay safe during a terrorist attack involving firearms and other weapons.
Run, hide, tell... police instructions on what to do during a firearms attack.Run, hide, tell... police instructions on what to do during a firearms attack.
Run, hide, tell... police instructions on what to do during a firearms attack.

It has been shared on social media by police forces across Yorkshire and the rest of the UK during the last few days.