A graphic British public service announcement about the dangers of sending text messages while driving has become an internet hit and sparked debate around the world.
The Gwent police force in Wales said that an excerpt from a video it made for use in schools has been viewed more than six million times on YouTube and other websites since it was posted last month.
The 30-minute film shows a bubbly teenager named Cassie - "a nice girl from a nice Gwent Valleys family" - who triggers a pileup that kills four people when she tries to send a text message while driving. The graphic, slow-motion depiction of the crash shows heads going through windshields, bloodied bodies and the lifeless eyes of a baby.
Talking on a hand-held mobile phone and texting while driving are both illegal in Britain.
"The film is hitting home because it has a hard edge and it taps into something that lots of people do but know they shouldn't," said the film's director, Peter Watkins-Hughes.
The film has been discussed on television shows in the United States, where more than a dozen states have banned text messaging while driving and where legislation is before Congress that would forces states to ban drivers from texting or emailing.
Recent studies suggest text messages may be more distracting to drivers than talking on the phone.
Research by British motorists' group the RAC Foundation found that texting slowed young drivers' reaction times by 35 per cent, more than drugs or alcohol.
A study of truck drivers released last month by the Virginia Tech Transportation Institute found that texting increased the risk of collision by 23 times - significantly more than the increase from talking on a cell phone.
Gwent Chief Constable Mick Giannasi said the issues in the film "are as relevant to the people of Tennessee as they are to the residents of Tredegar," the Welsh town where it was shot.
"Texting and driving can have tragic consequences and the more this film is viewed, the better," he said. "Young people think they can text on autopilot because they do it so instinctively - for that reason we need to use strong imagery to get them to sit up and take notice."
Britain has a long tradition of hard-hitting public service ads, shown on television, radio, in movie theaters and more recently on the internet.
One recent anti-speeding ad showed the bloodied and mangled body of a young girl who has been hit by a car. Another, discouraging binge-drinking, showed a young man in a superhero costume falling to his death.
While most comments posted in response to the Gwent police video praised its impact, some questioned whether such graphic images are necessary, or an effective deterrent.
Watkins-Hughes said he hoped his film would help make text-driving as socially unacceptable as driving while drunk.
"If we can get one person to change their behaviour then it will have been worthwhile," he said.