Watch: When royal guard fainted while holding vigil around Queen's coffin | VIDEO

London, Sep 15: A video of royal guard keeping vigil next to Queen Elizabeth's coffin collapsing is widely shared on various social media platforms. In the disturbing footage, the man appeared to stumble a few times before collapsing off the stage, landing face first as several onlookers rushed to his aid.

The incident happened during a vigil at Westminster Hall, where the Queen's coffin is lying in state at the Palace of Westminster for the next four days till the funeral on Monday. She was brought to London yesterday from Balmoral, where she breathed her last on Friday.

The Queen's coffin has been placed on a raised platform - or catafalque - and each corner is guarded through the day by a vigil of units from the Sovereign's Bodyguard, the Household Division or Yeoman Warders of the Tower of London. Hundreds of thousands of mourners are queuing up to pay their final respects to the monarch.

As the shocking footage spread across social media, many expressed concern for the guard's well being following the medical episode.

However, some users said that the man may have suffered from 'syncope' - a temporary loss of consciousness usually related to insufficient blood flow to the brain - caused by locking knees.

Local media outlet Express UK reported the guard was taken away for treatment.