At least 14 people have been injured after two cars collided and ploughed into spectators in a 'boy racer' collision in Stevenage last night.
Footage shared on social media showed a blue car hurtling past another vehicle and smashing into a crowd of youngsters on the central reservation of the A602 in Hertfordshire.
The blue Nissan clipped the slower-moving vehicle and sent it ploughing into another group of spectators on the pavement who were among hundreds of visitors at a Thursday night car meet.
The crash left the panicked spectators - many of them teenagers - screaming for help as a fleet of police and emergency vehicles arrived and a helicopter landed at the scene to help the stricken victims.
Hertfordshire Police said 14 people were being treated, some of them seriously injured, in the aftermath of the horrific crash as witnesses described rescue workers struggling to lift a car off a trapped victim.
A spokesman for the East of England Ambulance Service said 12 injured patients had been taken to three hospitals including the Lister Hospital in Stevenage.
Collision: The blue Nissan on the right hurtles along the right-hand lane of the A602 in Stevenage, clipping the slower-moving black vehicle on the left and sending them both crashing into spectators at a Thursday night car meet
Emergency response: More than a dozen ambulances and police cars gathered at the scene after the collision last night
Stricken: The blue vehicle, believed to be a Nissan 350z, is seen with its chassis and windscreen damaged after the crash
Panic: A crowd of people react in horror after watching the sickening collision at a car meet event in Stevenage last night
A diagram showing how the collision took place on the A602 in Hertfordshire as two cars ploughed into car meet spectators
An air ambulance was at the scene in the aftermath amid a huge emergency response with at least a dozen ambulances and police cars at the side of Monkswood Way.
The blue car, believed to be a Nissan 350z, was seen with a smashed windscreen in footage taken in the moments after the collision which also showed a crowd of people screaming for help.
Another video showed cars building up terrifying speeds in the moments before the impact, with spectators gathered in Stevenage for a Thursday night car meet which organisers insist was meant to be 'static'.
Ciaran O'Connor, 33, was in his car when he saw a group of children 'go flying' as the car rammed into them, saying the vehicle was hurtling along at 50mph.
'There was literally no time to react,' he said. 'If we were five seconds later we would have been involved in it. I'm just praying that no-one's been killed.'
He told MailOnline: 'They were all between the ages of 14 and 17. It was horrible. The car going faster on the other side of the road went into about another five people.
'Some boy got his arm stuck under the car and I saw people actually trying to lift the car up.'
Mr O'Connor said that there were roughly 250 teenagers lining the side of the road for the usual Thursday car meet-up.
One mother arrived to find her son injured and burst into tears, and that one person was lying 'motionless', he said.
Moments from disaster: The black vehicle turns into the left-hand lane of the A602 just seconds before it is struck by the faster-moving blue vehicle, sending it into spectators
Police presence: A line of officers at the scene last night after a collision which has left at least 12 injured people in hospital
Lit up: The blue lights of ambulances and police cars dominate the scene in Stevenage in the wake of the horrific crash
Emergency: Police vehicles respond to the crash in an emergency response which also saw an air ambulance arrive
The singer, from Stevenage, said: 'I've never seen anything like it in all my life. It was carnage. Kids were crying, I felt helpless. I got out of my car but what could I do.'
Rix Sidhu, 29, leads the Cruise Herts car club which organised last night's meet up.
He insisted that the group are not boy racers but 'car enthusiasts' and that the event was ruined by a minority of the estimated 400 total attendees.
He told MailOnline: 'We don't condone street racing, we organise static meet-ups. We park up and walk about and admire the cars, we've even had families come in the past. We've been doing this for 10 years.
'But we can't control everyone and we don't promote this. We are not boy racers, we are car enthusiasts.'
Another witness said on Twitter: 'I've just witnessed that horrendous crash in £Stevenage, no more than 50ft away from me. I'm still trying to process it all.'
As well as the Lister Hospital, patients have been taken to Watford General Hospital and to the the Princess Alexandra Hospital in Harlow.
A police vehicle on the scene after the Thursday night collision in which at least 14 people have been injured
This footage of the car meet in Stevenage, which was described as a charity event, shows spectators on either side of the road before the collision
One report on social media said that at least 10 people had been hit with a large number of emergency services on the scene
Mr Sidhu said that after last night's horrific car smash, they will never hold the event again. He added: 'Our thoughts go out to the victims involved and thank you to those who helped.'
The collision took place near a Wickes DIY store on the A602 in Stevenage on Thursday evening, where a crowd of people was gathered on either side of the road watching vehicles come past.
The black vehicle, believed to be a Toyota GT86, turned out from a side road, just seconds before the blue Nissan came hurtling along at huge speed in the right-hand lane and crashed into spectators on the central reservation.
It clipped the slower vehicle, sending the black Toyota slamming into spectators on the pavement before the video cuts out.
The car meet was described on Facebook as an 'extra special meet' to raise money for families affected by stillbirth and miscarriage.
It was intended to gather funds for a charity called 4Louis which provides equipment and training to hospitals and medics involved in the death of a child.
Three ambulances and two police cars at the scene in Hertfordshire on Thursday night following the horrific crash
The car meet was described on Facebook as an 'extra special meet' to raise money for families affected by stillbirth and miscarriage
Visitors are invited to 'come along and spend your Thursday evenings with fellow car enthusiasts.'
Event organisers called it a 'strictly static' event and warned that 'any antisocial behaviour will not be tolerated'.
It is not yet clear whether the drivers involved were members of the Cruise Herts car club.
A Hertfordshire Police spokesman said: 'Police and other emergency service colleagues are currently at the scene of a serious road traffic collision on Monkswood Way Stevenage.
'Two cars were involved in the collision which occurred at around 9.45pm. There were a number of people in the area at the time and 14 people are being are presently being treated for injuries, some of which are serious.
'Officers from the Beds, Cambs and Herts road policing unit are investigating and emergency services are expected to remain at the scene for some time.'
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