Police have released a three-point plan for members of the public who get caught up in a terror attack.
At least seven victims were killed and 48 injured as three terrorists wearing fake suicide bomb vests ploughed through pedestrians on London Bridge in a white van before crashing the vehicle near Southwark Cathedral and stabbing passers-by at random with large knives.
Chaos ensued the attackers made their way to nearby Borough Market as people fled through the streets and threw objects at them to ward them off.
:: Follow latest live updates after deadly London attack
The three men were shot dead as armed officers arrived at the scene within eight minutes of the first emergency call.
Police issued advice on what to do if a terror attack occurs after 22 victims were killed and 64 injured when suicide bomber Salman Abedi struck outside the Manchester Arena last month.
Theresa May had placed the country under "critical" alert – the highest of its kind, indicating an attack is “imminent” - following the Manchester attack, but the threat level was reduced to "severe" after three days.
MI5 say the threat level remains severe following the London Bridge terror attack which killed seven and injured at least 48.
The Assistant Commissioner and Head of National Counter Terrorism Policing for the Metropolitan police, Mark Rowley, urged people to remain "calm and alert" if they spot a potential incident.
He said in a statement: “If you see anything that causes you concern, then let us know immediately, if you have suspicions about someone's behaviour call us.
"If you believe that you are in the midst of a terror attack, the police have devised a plan."
Here's what you can do:
Run
First run to a place of safety – it is advised not to surrender or negotiate.
Hide
If you cannot run, hide. Turn your phone off, or to silent – and take care to turn off vibrate too. If possible, barricade yourself inside somewhere.
Tell
Only when you are safe, should you tell the police by calling 999 (if you are a UK resident).
If you have witnessed something that could suggest a terrorist threat, you can report it by filling out a form, here.
