Ok, so just one stopped clock. I just liked the sound of the phrase.
Runaway military horses covered in blood? Sounds like a symbolic dream at the opening of a political novel.
BBC has more details:
We’ve started to put together a picture of how today’s events played out.
The Army told the BBC a group of horses and riders from the Household Cavalry were on an extended exercise ahead of a Major General’s Inspection - which was due to take place tomorrow in Hyde Park.
Every military unit taking part in the King’s birthday parade must pass a Major General’s Inspection in advance.
The group included six soldiers and seven horses.
During the exercise, the horses were spooked by noise from nearby building works. Four soldiers were thrown from their saddles, and five horses ran loose through London.
A memorable day for a lot of people, one feels.
Two of the horses were recovered 5 miles from their starting point, so at least they had a nice day out, got to see some sights.
So one might suggest that they were…Wyld Stallions?
Terrified out of their wits (not hard for a horse) and trying to get away from whatever scared them. Not really a nice day out. The bloody horse apparently collided with a tour bus, so some tourists will have a good tale to tell when they get home.
Yes,in retrospect my claim that horses enjoy urban tourism is looking a little foolish.
I’m not a superstitious man but there is no way this is not God giving a vote of “hard no” to Rwanda bill that was passed yesterday 
Not to mention galloping on pavement, especially the ones that got five miles away. There’s a real danger of road founder, a type of laminitis caused by excessive work on hard surfaces. They might also develop tying up (exertional rhabdomyolysis) – a painful muscle condition of the back and hindquarters caused by too much exertion for their level of fitness, which can take weeks to months to fully recover from.
I doubt it, but as they passed Aldwych House, they may have given some equine support to the Sub-Postmasters and a big neigh to the bosses at the Post Office.
An update: Two of the horses were indeed seriously injured (one of them likely the bloodied gray) and have had surgery:
“Two of the injured horses were operated on last night, with one transferred to an equine hospital,” said the British Army on X Thursday.
“Our horses receive the highest standards of care, and those that did not undergo surgery are expected to return to duty in due course.”
How were they injured? The story doesn’t specify, but
According to Britain’s PA Media news agency, a Mercedes taxi that was waiting outside the Clermont Hotel on Buckingham Palace Road had its windows smashed by the spooked horses, while one of the animals shattered the windscreen of a double-decker tour bus.
Between the collision injuries and what I suggested above about road founder and tying up, I would not be surprised if neither horse ever returns to duty, indeed it’s quite possible that one or both may have to be euthanized.
Or a Patti Smith song.
I saw the construction chute that spooked them on the news. It looked like dirt, not debris coming out of it, meaning it might be one of those Super-basement projects
So what’s the stopped clock?
“While the pandemonium was underway, the clock in the Elizabeth Tower — more commonly known as Big Ben, the city’s most recognizable landmark and usually an icon of stability — stopped without explanation at 9 a.m.”
Spooky!
Not unexpected.
But I really hope the horses come through OK.
Hay! There’s no horsing around at the SDMB 
The news appears to be encouraging
Thanks for the update! I’m glad to learn that Quaker, the black horse, is doing so well. Sounds as if he may recover fully and go back to his duties. Quaker, the grey… not so encouraging that he’s still under intensive medical observation. Even if he does pull through and regain good health, it wouldn’t surprise me if he’s retired from active duty.