Epsom is usually a fairly quiet suburb in Surrey, but over the last couple of weeks it's been at the centre of violent disorder.

Protesters took to the streets, many demanding answers from Surrey Police about the suspects in an alleged gang rape and some suggesting asylum seekers or immigrants were involved.

Vandalism took hold and arrests were made, with protesters even entering a local hotel they mistakenly believed was housing migrants.

Except police now say the alleged gang rape never happened.

Following a "thorough investigation", Surrey Police believes the woman who made the report of rape "sustained an accidental head injury" following a night out and made "a confused report". She had given officers permission to share that information - and the force says it takes every report of sexual offending seriously.

How did this happen, and could it happen again? All evidence points towards online misinformation and then a real-world frenzy - and I've been investigating it for the BBC's Top Comment podcast.

Surrey Police issued a public appeal for witnesses on 12 April, saying that an alleged rape had taken place outside a church in the historic market town, south west of London, in the early hours of the previous day.

The force said it had received reports a woman in her 20s had been attacked on her way back from a nightclub.

Last year, new guidance was issued by the National Police Chiefs' Council (NPCC) encouraging forces to consider disclosing the ethnicity and nationality of suspects in high-profile cases in a bid to reduce the spread of misinformation.

Surrey Police says its initial appeal about alleged suspects lacked this information "because the descriptions given were vague and limited".

The force simply didn't seem to have the details to follow the NPCC guidance.

But since that guidance was released, some people have come to expect these kinds of details to be released immediately. So what happens when they aren't?

Misinformation about the Epsom incident began to circulate online, with many accounts on social media making false suggestions the suspects were asylum seekers or migrants. Others commented that they were distressed by reports of such a serious crime taking place in their local area, and expressed support for the alleged victim.

But these conversations were eclipsed by posts on X from influential accounts - those which pay for blue ticks to give their posts greater prominence in the platform's algorithm - alleging police cover-ups and suggesting they had intel about the suspects' identities.

Sander Van Der Linden, a professor of social psychology at the University of Cambridge, uses the term "stochastic terrorism" to describe events like this.

"[This] is basically the likelihood that online ideologically-driven misinformation results in offline harm and violence. Anti-immigration misinformation in particular has an increasingly high chance of turning violent," he says.

In the week that followed the police appeal, a protest took place. Some locals attended and asked questions about what had happened. Others taking part seemed to have arrived from outside Epsom. People demanded descriptions of the suspects.

One popular X account, Inevitable West - which I've investigated before and appears to be based outside the UK - shared clips of the protest and claimed "ALL of Britain backs these patriots". That post reached more than half a million users - showing how rage bait posts are prioritised by some algorithims.

Several days after the initial appeal for witnesses, Surrey Police said it had not found evidence that the offence happened "as reported," and explicitly said there was "no evidence" asylum seekers or immigrants were involved.

But that did little to quell the online outrage.

One local Facebook group was so overwhelmed by content that its admins were forced to issue a warning that the forum "was never intended to become a place for hatred, hostility and deeply unpleasant behaviour to reside".

Another viral post with almost half a million views claimed, without any evidence, that the parents of the young woman at the centre of the allegations were being silenced - and had been told they were "not allowed to talk to the media" and "will be arrested if they do".

It went on to ask: "Is this country finished?"

Unrest escalated once again this week, with group of protesters descending on Epsom a second time. Clips show several shouting "get them out" and entering a local hotel, which did not house immigrants. The arrival of riot police led to posts suggesting protesters were being treated unfairly.

Five people, aged between 15 and 23 from across Surrey and London, have now been arrested on suspicion of public order offences and criminal damage after "missiles" were thrown at officers.

Yet more videos of protests went viral, prompting questions about what was real and what was AI-generated.

Without having any real facts about the case, people shared emotive speculation and mistruths playing into fears about immigration - which Surrey Police said had caused "concern" within the community.

The online chatter only calmed down when the force eventually revealed this week that "no sexual offence had occurred" and its investigation was closed.

Police and Crime Commissioner Lisa Townsend said it would "not have been appropriate to provide a running commentary on the investigation at such a delicate stage until all enquiries had been completed".

But she acknowledged "there are, of course, always lessons to be learnt" when it comes to what the police put in the public domain.

"Sadly, this situation was exploited by some who used legitimate concerns local residents may have had around the safety of women and girls in our communities to push a far more sinister narrative," she said.

"Instead of exercising some degree of patience and restraint and letting the police do their job to establish the facts, we had numerous social media commentators, politicians and 'experts' lining up to give their theories on a case they had limited knowledge of. Many of them quite frankly should know better."

The sequence of events in Epsom demonstrates the power of social media algorithms.

When algorithms are designed to reward rage bait content - by regularly pushing it onto other users' feeds - it can have the real-world impact of shaping and distorting people's beliefs. X did not respond to the BBC's request for comment for this article.

There are parallels here with the violent disorder that unfolded in Southport in 2024 after Bebe King, Elsie Dot Stancombe and Alice da Silva Aguiar were murdered at a dance class.

Some seized upon the sparse details about who had committed that horrific attack, to falsely claim the perpetrator was a Muslim asylum seeker - sparking even more rage in the process.

Following the furore in Epsom over a crime that did not happen, it appears neither the police nor social media giants know what to do when there's insufficient verified information to satiate a public hunger to know the details of serious crimes immediately.