This is the moment a Royal Navy sailor collapsed on Whitehall during a rehearsal for King Charles' Coronation.
Hundreds of soldiers from the military, navy and RAF marched through central London before stopping along Whitehall and standing in silence in the early hours of Wednesday.
Many carried a wide range of instruments such as saxophones, trumpets, horns and cymbals but only the drums were played by marching soldiers until they returned down the Mall after 3am.
Footage taken shortly beforehand, at around 2.15am, shows a woman having to be helped from the ground after struggling during the training.
Concerned colleagues rushed to her aid before she was escorted from the area.
An onlooker who filmed the clip, and wished to remain anonymous, said: "I felt really privileged to see [the practice].
"I just wanted to show people how hard they are working - it shows how committed they are. It was wonderful to watch them practicing and it felt very special to be seeing it before anyone else.
"I was just panning across when I noticed her fall down. I hope she's okay - I felt awful for her."
Footage later shows a stretcher being brought over for the sailor, but she stood up again and didn't need it.
"Someone very important looking came over to help her," the eyewitness added. "They were all very professional."
A Royal Navy spokesperson said: "We are very proud of our personnel who are working incredibly hard at this time.
"Their training has been scheduled to condition personnel in a measured way for the rigours of long periods of standing and marching.
"This is an intense period for them, and significant periods of rest have been scheduled before and after major periods of activity."
It's understood the woman, whose identity is unknown, fully recovered and continued to train.
The King's Coronation takes place this Saturday and will see the largest military ceremonial operation for 70 years, including more than 6,000 members of Britain's armed forces.
As part of preparations for the full event, the Diamond Jubilee State Coach and Gold State Coach were marched down the Mall.
The Diamond Jubilee State Coach was accompanied by hundreds of soldiers on horseback as it travelled along the Mall, setting off shortly after 12:20am on Wednesday.
Royal fanatics waited for over three hours for the parade to make a return journey down the Mall.
Crowds ran through St James' Park to find the best spots near the palace with many trying to spot their relatives in their military outfits.
The parade had began when soldiers dressed in bright yellow uniforms began the short journey and the brass band on horseback practised as they accompanied the stage coach as it passed through Westminster.
Onlookers skipped along next to the stage coach and ran after the regiments of mounted soldiers that followed.
Soldiers from a wide variety of regiments marched down the Mall after 1am.
Buckingham Palace remained mostly silent with soldiers quietly maintaining protocol until a regiment playing the bagpipes brought the area to life shortly after 2.30am.
At least 15 tents are already positioned along the Mall and royal fans got to test their viewpoint as they prepare to camp out until Saturday.
John Loughrey, 68, claimed to be the first person to set up his tent on the Mall on April 27, nine days before the Coronation.
He said: "We like the build up, the rehearsals and seeing people throughout the day.
"There are a lot of tourists and they come and say they wish they had something like this in their country."
Mr Loughrey explained he had been camping outside royal events for 26 years and spent a month camping out after Princess Charlotte was born.
He added: "We did a lot of research. We (picked this spot) because there are no trees so you can see the Red Arrows."
Other soldiers were spotted parading in Parliament Square and practised changing position as Big Ben chimed.
Artillery regiments rehearsed moving cannons on horseback and soldiers were seen pretending to fire the ceremonial weapons.
The procession returned to Buckingham Palace shortly after 3am with bands in full swing. The Gold State Coach was later spotted passing Buckingham Palace at around 3.20am.
