Police in the United States say dozens of people have died as the result of a high-speed craze which is now out of control.
An explosion in the number of illegal street races and so-called "side-shows" is partly down to the ease with which they can be organised and broadcast on social media.
In Southern California, a hotbed of street racing, tech-savvy drivers are winning the deadly game of cat-and-mouse even when confronted by a new multi-agency police task force.
Sky News has witnessed the craze from the perspective of those taking part, the officers trying to stop it and those grieving for the victims.
The events usually happen in the early hours of the morning and take various forms.
Drag races between two cars are arranged between drivers, they bet a cash prize often running into the thousands and then race over an eighth-of-a-mile straight stretch of a public road.
Two weeks ago a man was killed and a woman critically injured when they pulled out of a junction into the path of a car involved in an illegal street race.
"Side-shows" are also known as "take-overs". A crowd will block a junction, enabling drivers to take it in turns to perform high-speed "donuts" or "burnouts" as spectators try to get as close as they can.
The crowd often prevents police from reaching the scene and officers have been assaulted trying to break up events. Even being a spectator at a side show can lead to arrest.
An even more dangerous variant are the impromptu street races that take place between drivers who challenge each other on busy motorways.
While drivers and spectators are among the dozens who have died, a large number were innocent victims in the wrong place at the wrong time.
Michelle Littlefield was on her way home from a day out with friends at Disneyland when their car was struck by a truck which had been sent out of control by a driver allegedly racing another car.
The 19-year-old's parents now campaign for stronger action to be taken.
Willy Littlefield told Sky News: "He stole my daughter. These people need to wake up and take that conscious moment. In this case, street racing meant death, pain, prison and coma. It's not nice."
Michelle's mother Gigi said they had been robbed of a young woman who was "full of dreams".
1:22The couple say the makers of movies and car commercials have a responsibility to not glamorise high-speed driving on crowded streets.
Street racers describe the excitement and danger, the adrenaline and ego of illegal events.
Street racer Fabian Arroyo says there is an answer. He told Sky News: "We don't want to see people die. Instead of doing it in a crowded place and killing other people, pick a remote area where nobody is around and go race. If you kill someone it's just yourself."
The challenges facing police were all too evident during a major operation run by LA's street racing task force on a night racers label their 'Super Bowl'. Dozens of officers were involved but just a handful of tickets issued.
A "burnout" involving 50 cars was being live streamed by one of the spectators on social media. By the time police arrived at the location, cars were leaving.
Officer Juan Galvan, with the California Highway Patrol, said: "It's a cat-and-mouse kind of thing. Even though we have offices scattered throughout the whole county, they tend to move locations and we can only get there so fast."
"But we're out here ready for it."
Sky News will broadcast a special report called STREET RACING: AMERICA'S DEADLY PURSUIT on Tuesday at 0930, 1130, 1430, 1630, 1930 and 2130
Police in the United States say dozens of people have died as the result of a high-speed craze which is now out of control.
An explosion in the number of illegal street races and so-called "side-shows" is partly down to the ease with which they can be organised and broadcast on social media.
In Southern California, a hotbed of street racing, tech-savvy drivers are winning the deadly game of cat-and-mouse even when confronted by a new multi-agency police task force.
Sky News has witnessed the craze from the perspective of those taking part, the officers trying to stop it and those grieving for the victims.
The events usually happen in the early hours of the morning and take various forms.
Drag races between two cars are arranged between drivers, they bet a cash prize often running into the thousands and then race over an eighth-of-a-mile straight stretch of a public road.
Two weeks ago a man was killed and a woman critically injured when they pulled out of a junction into the path of a car involved in an illegal street race.
"Side-shows" are also known as "take-overs". A crowd will block a junction, enabling drivers to take it in turns to perform high-speed "donuts" or "burnouts" as spectators try to get as close as they can.
The crowd often prevents police from reaching the scene and officers have been assaulted trying to break up events. Even being a spectator at a side show can lead to arrest.
An even more dangerous variant are the impromptu street races that take place between drivers who challenge each other on busy motorways.
While drivers and spectators are among the dozens who have died, a large number were innocent victims in the wrong place at the wrong time.
Michelle Littlefield was on her way home from a day out with friends at Disneyland when their car was struck by a truck which had been sent out of control by a driver allegedly racing another car.
The 19-year-old's parents now campaign for stronger action to be taken.
Willy Littlefield told Sky News: "He stole my daughter. These people need to wake up and take that conscious moment. In this case, street racing meant death, pain, prison and coma. It's not nice."
Michelle's mother Gigi said they had been robbed of a young woman who was "full of dreams".
1:22The couple say the makers of movies and car commercials have a responsibility to not glamorise high-speed driving on crowded streets.
Street racers describe the excitement and danger, the adrenaline and ego of illegal events.
Street racer Fabian Arroyo says there is an answer. He told Sky News: "We don't want to see people die. Instead of doing it in a crowded place and killing other people, pick a remote area where nobody is around and go race. If you kill someone it's just yourself."
The challenges facing police were all too evident during a major operation run by LA's street racing task force on a night racers label their 'Super Bowl'. Dozens of officers were involved but just a handful of tickets issued.
A "burnout" involving 50 cars was being live streamed by one of the spectators on social media. By the time police arrived at the location, cars were leaving.
Officer Juan Galvan, with the California Highway Patrol, said: "It's a cat-and-mouse kind of thing. Even though we have offices scattered throughout the whole county, they tend to move locations and we can only get there so fast."
"But we're out here ready for it."
Sky News will broadcast a special report called STREET RACING: AMERICA'S DEADLY PURSUIT on Tuesday at 0930, 1130, 1430, 1630, 1930 and 2130
