The First Minister has praised the work of police "across the country" following the terrorist attack in Westminster.

Nicola Sturgeon spoke at Holyrood during First Minister's Questions on Thursday, where opposition leaders also discussed the incident.

The attack outside the Palace of Westminster left four people dead, including the attacker, and 40 injured. Unarmed police officer Keith Palmer was among those killed.

The Islamic State terror group has claimed the attacker was one of their "soldiers."

Sturgeon told the MSPs: "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 officer 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'."

She said there was no specific intelligence to suggest Scotland faced an increased risk of terrorist attacks but security was being raised at several locations including Holyrood.

She continued: "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 [Theresa May].

"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."

Scottish Conservative leader Ruth Davidson also expressed her "deep shock" at what had happened.

She said: "Yesterday, a coward killed three innocent people and injured many more in an attempt to attack the symbol of our country's democracy.

"His attack on our values failed as he died by the paramedics who demonstrated what a civilised society is by trying to save him.

"His attack on our freedom will fail again today as we show our resolve by returning to work and getting on with our lives."

Scottish Labour leader Kezia Dugdale said: "No matter the religion, nationality or identity of the attacker, this cannot and must not turn into a war on any one community.

"Bringing people together must be part of the solution to tackling terror, rather than creating further division within communities.

"We must send a strong message that Britain remains an open and tolerant nation that is home to people of all faiths and nationalities."