Britain's political parties have suspended national general election campaigning in the wake of the London Bridge attack, which killed six people.
Labour, Conservatives, Lib Dem, Green and SNP spokespeople announced on Sunday morning that they would temporarily stand down.
Major political programming including the BBC's Andrew Marr Show and the Sunday Politics have also been taken off the air in light of the attack, to be replaced by rolling television news.
Local campaigning and door-knocking around the country is understood to be continuing in a limited capacity despite the national media shutdown, however.
A spokesman for the Conservative Party said: "The Conservative Party will not be campaigning nationally today. We will review as the day goes on and as more details of the attack emerge.
Labour leader Jeremy Corbyn said: “We are all shocked and horrified by the brutal attacks in London. My thoughts are with the families and friends of those who have died and the many who have been injured. Today, we will all grieve for their loss.
“I would like to thank the police and emergency services for their bravery and professionalism in acting to save lives and deal with these appalling acts of terrorism, as well as NHS staff and members of the public who sought to protect others.
“The Labour party will be suspending national campaigning until this evening, after consultations with other parties, as a mark of respect for those who have died and suffered injury.
“Those who wish to harm our people, divide our communities and attack our democracy will not succeed. We will stand together to defend our common values of solidarity, humanity and justice, and will not allow terrorists to derail our democratic process.”
Mayor of London Sadiq Khan has said he does not believe the general election should be postponed due to the attack, however. The election is scheduled for 8 June, this Thursday.
In the aftermath of the Manchester Arena attack, the major political parties suspended national campaigning for three days.
At least six people died and more than 48 were injured when three suspects ploughed a vehicle into pedestrians on London Bridge before attacking others in nearby tourist hotspot Borough Market.
The Prime Minister will chair a meeting of the Government's Cobra emergency committee on Sunday in response to the tragedy.
Ms May said: “Following updates from police and security officials, I can confirm that the terrible incident in London is being treated as a potential act of terrorism.
“This is a fast moving investigation. I want to express my huge gratitude to the police and emergency services who are on the scene. Our thoughts are with those who are caught up in these dreadful events.”
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