Gardaí have issued a warning about a new social media challenge which is encouraging people to lie on a road with a sheet over them to stop oncoming traffic.
The online trend, called 'ghosting', has already seen one girl hospitalised with injuries in the south of the country in recent days.
A Government TD has also warned that the challenge will cost lives if it continues.
Gardaí are now urging people not to engage in 'ghosting' and appealed for parents to educate their children on the dangers of lying on a road with a sheet covering them.
In a statement they said: "An Garda Síochána has been made aware of a social media trend circulating online called 'ghosting'.
"This ongoing trend challenges persons to lie on a roadway with a sheet placed over them in an attempt to stop oncoming traffic.
"This activity is extremely irresponsible and poses a serious danger to those taking part in the 'ghosting' and motorists.
"Gardaí attended an incident in the southern region in recent days where a youth received a number of minor injuries while participating in this activity.
"Emergency services escorted the youth to hospital where she is being treated for injuries sustained to her back, torso and ankle.
"She was admitted to hospital for a number of days."
Fine Gael TD Emer Higgins has also warned that the trend could cost lives and that it must be stopped.
The Dublin Mid West TD said: "The latest social media challenge called ghosting is on the rise in Ireland and has gardaí rightly concerned.
"Make no mistake, this challenge will cost lives. I implore young people to think twice before ghosting cars, cyclists and other road users.
"As well as leaving themselves at risk of being knocked down, they could cause a car to hit another car or vulnerable road user.
"Already we have seen one young Irish social media user hospitalised over this and I wish her a speedy recovery.
"I hope young people all over Ireland can learn from this and give up this dangerous challenge.
"Ahead of the school Christmas break there may also be an opportunity for a discussion on road safety in the classroom and I encourage teachers to take up these issues with young people to start the discussion," Ms Higgins added.