One of the Royal guards watching over the Queen's coffin at Westminster Hall collapsed suddenly overnight.
The guard was standing at the foot of the late monarch's casket when he fell to the floor.
Footage taken from a live broadcast which was posted to social media at around 01:00 captured the incident.
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The black-clad guard was holding a ceremonial staff when he appeared to faint, with nearby officials quickly rushing to his aid.
As he was tended to, the live vision quickly faded to exterior, night-time shots of the building. Over an hour later, the broadcast had still not returned to the scene inside the hall.
Soldiers in ceremonial uniform are maintaining a constant, 24-hour vigil around the Queen's coffin while she is lying in state.
The guards from units which include the Sovereign's Bodyguard, the Household Division or Yeoman Warders of the Tower of London are required to remain completely still at the four corners of the catafalque.
While the soldiers rotate every 20 minutes, the complete shift for each soldier is six hours in length.
The incident happened on the first night of the Queen's lying in state which gives members of the public the chance to pay their respects to the late monarch.