The people of London sent out a message of defiance and unity today, in the wake of a terror attack on Westminster that left four dead.
Commuters went about their business as usual in the capital, as the hashtag #WeAreNotAfraid trended on Twitter. The London Underground sign emblazoned with these words (above) also went viral.
At tube stations across London, staff used white service information boards to share messages of hope, solidarity and courage. Their quotes were accompanied by hashtags such as #LondonIsOpen, #Westminster #WeAreNotAfraid and #IAmLondon.
The British "lone actor" attacker involved in Wednesday's incident left three people dead and a further 29 in hospital after he mowed down crowds gathered around Westminster Bridge.
Armed with two knives, he then ran at the gates of the Houses of Parliament - where he stabbed and killed police officer Keith Palmer - before being shot dead by firearms police.
The attacks, which occurred at a very busy time just after the weekly Prime Minster's Questions session in Parliament, brought to the fore a number of extraordinary acts of heroism.
Amid the chaos unfolding on Westminster Bridge, many people were pictured rushing to the help of strangers, performing CPR and providing comfort with no regard to their own personal safety.
MP Tobias Ellwood, Britain's foreign minister, spent 15 minutes attempting to save the life of the police officer who was stabbed. He lost a brother in the Bali terror attacks of 2002.
The Met Police said today that they believed the attacker was acting alone. However, they have made a number of arrests in association with the incident in Birmingham, London and elsewhere overnight.
The so-called Islamic State (Isis) has claimed responsibility for the attack.
Public figures shared Londoners' spirit of calm and stoicism in light of the attacks.
"After a tragic day in Westminster, our democracy continues tomorrow. Terrorism will never defeat us. #WeAreNotAfraid," said Will Quince, MP for Colchester.
Prime Minister Theresa May paid tribute to the "exceptional men and women" of the police force who responded to the attack, saying: "We will all move forward together, never giving in to terror and never allowing the voices of hate and evil to drive us apart."
Mayor of London Sadiq Khan spoke for many when he said: "My message to those that want to harm us and destroy our way of life is: You won't succeed; you won't divide us; we won't be cowed by terrorists."