The First Minister Nicola Sturgeon delivered the below statement ahead of First Minister's Questions at the Scottish Parliament.
Let me express - on behalf of the chamber and our country - my shock and sadness at the heinous attack on Westminster yesterday afternoon.
We send our heartfelt condolences to those who have lost loved ones, and our thoughts to all those who sustained injuries.
Many of us in this chamber have friends and colleagues, indeed some of us have family members, who work within the Palace of Westminster - parliamentarians, staff and journalists. Yesterday was a harrowing day for all of them - and they have our support and good wishes.
Above all, we stand in solidarity with London - a vibrant, diverse, wonderful city that will never be cowed by mindless acts of violence.
This attack stands, of course, as a stark reminder of the dangerous jobs that our emergency services do every day on our behalf.
Yesterday, a Metropolitan police office went to work to protect and defend democracy and did not return home.
Our thoughts and prayers are with the family of PC Keith Palmer.
However, today we should also express our appreciation to police men and women across the country who risk their lives every day in the line of duty.
To the police and security staff who keep us safe here in our own parliament, we say thank you.
In the aftermath of the attack yesterday, I was updated by the National Security Adviser and also on the immediate actions taken by Police Scotland.
I convened a meeting of the Scottish Government's Resilience Committee last night.
That was an opportunity to review what was known about the events in London, consider any implications for Scotland and hear directly from the Chief Constable and other senior officers about their response.
I am grateful to the Chief Executive of our Parliament for taking part in that meeting.
It is important to stress that there is no intelligence of any increased threat or risk to Scotland.
However, as a precautionary measure, Police Scotland have increased security at key locations - including our parliament - and will keep these arrangements under review.
The public should also remain vigilant - but go about their everyday business as normal.
We know that, at times like these, it can be all too easy to look for someone to blame.
It is important therefore that we are very clear about this:
Acts of terrorism are not the responsibility of any one faith or section of our society.
The only people to blame for acts of terrorism are the individuals who plan and perpetrate them.
Let me end by echoing and endorsing the words of the Prime Minister.
Terrorists seek to undermine our values and destroy our way of life.
They will not succeed.
Whatever our disagreements in this chamber or any other, we stand united in our core values of democracy, human rights and the rule of law.
Those values are strong and they will endure.