At least 17 people have been injured after “rogue racers” crashed into a crowd of car enthusiasts who had gathered in Stevenage.
Hertfordshire police said some of those being treated were seriously hurt.
Organisers of the event said they had urged participants to stay off the roads, but “some people went a bit rogue”.
One witness described seeing bystanders “panicking, screaming” as the crash happened.
One of the cars involved in the crash
The incident happened at about 9.45pm during a Cruise Herts car meet which has been running for 17 years.
The meets appear to be a weekly event at a retail car park in the town.
They are billed as a “strictly static” event, which means vehicles are supposed to remain parked, drivers are allowed to rev their engines and show off the modifications they have made.
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But footage from last night clearly showed cars speeding just metres from gathered crowds on a road, young people in particular, with their phones out and filming what was happening.
Sky reporter Katerina Vittozzi, at the scene, said: “Organisers told me that some of the people that showed up were not regular attendees and decided to go to a road outside of the car park and start racing.”
As people lined Monkswood Way – a single-carriageway of section of A-road in a non-residential area – two vehicles collided before careering into bystanders, with at least one speeding.
Video shows one car turning left onto the section from a side road, when another speeds past and clips the slower vehicle, sending both veering off in opposite directions.
Crowds were standing at the side of the road and on the central reservation before the crash.
Witness Ciaran O’Connor, who lives in the area and said he was being driven home by a friend, described a scene of fear and shock.
“We saw all these people standing on the road. Then, we came round and saw the car going straight into these kids who were standing by the side of the road,” he told Sky News.
“Everyone was panicking, screaming, there were a lot of kids there, loads of teens actually, about 16, 17, 18 years old.
“Everyone was screaming and just shocked. I felt so sorry for the kids who had to see it. There were so many of them there.”
Mr O’Connor said he saw people “badly injured” and that police arrived at the scene within five minutes of the crash.
Emergency services at the scene
Organiser Rix Sidhu said he felt “sick” afterwards. “To see people on the floor not able to move, it wasn’t a nice sight.”
He said: “We are devastated. I’ve been running this for 10 years and we have never had one incident.
“We were raising money for charity, as we often do, and there was no speed element to it.
“We held the meet in a car park with a speed bump at the entrance. But unfortunately some people went a bit rogue.
“We try and stop that, we urge people – urge them on social media beforehand – not to go out on the roads, not to risk injury or anything.
“But unfortunately, in this age of social media and Snapchat, people want to get footage and post things to their friends, which seems to drive some people to the main road.
Crowds are seen standing at the side of the road and on the central reservation
“We have a liaison officer to pass number plates to police if there is ever any trouble; we try to make it as safe as possible.
“Some people like drinking and that sort of thing, we just like cars. They are our pride and joy, what we are interested in.
“Unfortunately this incident means we are all going to be tarred with the same brush – people will say we are boy racers.”
He added: “But we’ve decided we’re not going to run these any more. After 17 years, it’s over.”
Mr Sidhu said events are normally staged in cooperation with the police.
Hertfordshire Police told Sky News the force was unaware of this particular event, but officers responded within minutes of the collision being reported.
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The area where the crash happened reopened on Friday after emergency services had left the scene with all police tape and debris cleared away.
The only sign of the incident were police road markings showing the points at which the cars collided and ended up crashing into the crowd.
A spokesperson for the East of England Ambulance Service said the injured had been taken to three hospitals – the Lister Hospital in Stevenage, Watford General Hospital and the Princess Alexandra Hospital in Harlow.
An air ambulance attended the crash and emergency services remained on site late into the night.
:: Police have appealed for witnesses and urged anyone with footage of the incident to keep hold of it and email it to [email protected]