A man has been taken down by police and led away after making a run towards the Queen's coffin at Westminster Hall.
Other mourners looked on in horror and there were gasps as the man broke from the line of people and headed for the coffin.
Police and officials reacted quickly to grab the person in the hall at 10pm on Friday night and he was arrested.
Tens of thousands of people have been queuing to pay their respects to the late Queen at Westminster Hall with the line running for many miles and mourners told it could take over 12 hours before they get to the front.
Met Police said: “22:00hrs on Friday 16 September officers from the Met's Parliamentary and Diplomatic Protection Command detained a man in Westminster Hall following a disturbance.
"He was arrested for an offence under the Public Order Act and is currently in custody.”
READ MORE: Top presenter blasts RTE for Queen Elizabeth funeral decision
Mourners can continue to view the coffin until 6.30am on Monday morning before the funeral later that day.
Officials believe the Queen's funeral will be the "largest international event" the UK has held in decades, possibly ever.
Around 500 dignitaries from around the world are expected to attend - with US president Joe Biden, French leader Emmanuel Macron and New Zealand's premier Jacinda Ardern among those making the trip to Britain for the occasion.
Many of the mourners filing past the coffin during the vigil bowed their heads, while some had tears in their eyes.
One woman who was weeping was comforted by a member of staff before she left the hall.
Before leaving, many mourners turned to take one last look at the coffin and the silent vigil that was under way.
The King and his siblings stood in silent contemplation as they guarded their mother's coffin in Westminster Hall on Friday shortly before 8pm.
The Queen's children - Charles, the Duke of York, the Princess Royal and the Earl of Wessex - took part in the vigil as a steady stream of mourners filed past to pay their final respects.
The sovereign, Anne, Andrew and Edward looked sombre as they took their places at the coffin - four days after they took part in a vigil in St Giles' Cathedral in Edinburgh.
The King stood at one end of the coffin, head down and hands clasped, while the Duke of York was at the opposite end facing the area where the queue of mourners enter the hall.
Other members of the royal family, including the Queen Consort, Vice Admiral Sir Tim Laurence and the Countess of Wessex, along with some of the Queen's grandchildren and great-grandchildren, looked on.
READ NEXT:
Fireball which lit up night sky was 'space debris', experts conclude
Crowds gather as long-awaited Penneys store opens in Tallaght, Dublin
Man claiming to be King Charles and Camilla's 'secret son' wrote to Queen demanding paternity test
Get breaking news to your inbox by signing up to our newsletter
