William Davies in The Guardian:
On a late Friday afternoon in November last year, police were called to London’s Oxford Circus for reasons described as “terror-related”. Oxford Circus underground station was evacuated, producing a crush of people as they made for the exits. Reports circulated of shots being fired, and photos and video appeared online of crowds fleeing the area, with heavily armed police officers heading in the opposite direction. Amid the panic, it was unclear where exactly the threat was emanating from, or whether there might be a number of attacks going on simultaneously, as had occurred in Paris two years earlier. Armed police stormed Selfridges department store, while shoppers were instructed to evacuate the building. Inside the shop at the time was the pop star Olly Murs, who tweeted to nearly 8 million followers: “Fuck everyone get out of Selfridge now gun shots!!” As shoppers in the store made for the exits, others were rushing in at the same time, producing a stampede.
Smartphones and social media meant that this whole event was recorded, shared and discussed in real time. The police attempted to quell the panic using their own Twitter feed, but this was more than offset by the sense of alarm that was engulfing other observers. Far-right campaigner Tommy Robinson tweeted that this “looks like another jihad attack in London”. The Daily Mail unearthed an innocent tweet from 10 days earlier, which had described a “lorry stopped on a pavement in Oxford Street”, and used this as a basis on which to tweet “Gunshots fired” as armed police officers surrounded Oxford Circus station after “lorry ploughs into pedestrians”. The media were not so much reporting facts, as serving to synchronise attention and emotion across a watching public.