A man handcuffed to gates at Buckingham Palace has "sustained a number of self-inflicted slash injuries" said police as they continue to negotiate with him.
The person wearing a white T-shirt and a baseball cap could be seen talking to police officers as people looked on in shock before they were evacuated at around 5.30pm today and the area was put into lockdown.
Police have said that the man, who also looks to have laid a book or folder of papers in front of himself, is believed to be in his 30s and "threatened to harm himself".
A later update at 9pm said that the man had "sustained a number of self-inflicted slash injuries".
There was very quickly a large police presence at the scene on Thursday evening as officers and paramedics began negotiating with the man and they were still talking with him at 10.15pm.
A person has tweeted footage of the incident in central London.
"Unfolding drama at Buckingham Palace where a man has handcuffed himself to the entry gates.. police on hand," she wrote.
In a second clip she shows people then being moved away stating: "Area surrounding the gate being completely cleared."
A police officer can also be heard telling people to "cross the road".
And the Twitter user wrote shortly before 6pm: "Immediate vicinity of gate completely cleared now."
And again 45 mins later, with the situation still not resolved, she tweeted: "Scene getting bigger at #buckinghampalace - now entire area in front of the palace cleared of usual crowds and tourists."
The Met Police said that they are trying to negotiate with the man.
A statement read: "At around 17:23hrs a man approached the gates of Buckingham Palace and handcuffed himself to them.
"Officers in the area immediately approached the man, believed aged in his 30s, who began threatening to harm himself.
"LAS are also on scene. Police are trying to speak to the man & bring the situation to a swift conclusion to ensure his safety and welfare."
Then a later tweet at 9pm read: "Cordons remain in place & situation still ongoing. Officers are still speaking to the man, who has sustained a number of self-inflicted slash injuries. Police are working to bring the situation to a safe end as quickly as possible."
It comes with King Charles having been in Scotland this week for his second coronation.
No member of the Royal Family currently lives at Buckingham Palace, which is undergoing extensive renovation works.
Charles was presented with the Honours of Scotland - the country’s crown jewels - during a service of thanksgiving and dedication on Wednesday at St Giles’ Cathedral in Edinburgh.
He was joined by his wife, Queen Camilla, as well as the Prince and Princess of Wales for the ceremony. It came eight weeks after Charles and Camilla were crowned in an ancient ceremony at Westminster Abbey, where the King made a pledge to "serve".
The Right Reverend Sally Foster-Fulton, Moderator of the General Assembly of the Church of Scotland, delivered the sermon, which took the environment as one of its themes.
She told the congregation that society will be on the "right track" if we understand that "the Heavens and Earth" are not "human commodities or possessions".
Charles and Camilla have been living at Clarence House since 2003, and reportedly have no plans to move into Buckingham Palace.
