The 17-second clip shows a Nissan Micra being driven at speed down a steep field, believed to be in the Clonakilty area of West Cork and leaping over a road before landing in another field.
The Road Safety Authority (RSA) has also condemned another clip posted on YouTube which showed young drivers in Nenagh hanging out of their cars while driving at speed along country roads.
The latest clip was shot in the general Clonakilty area and was posted on YouTube about a month ago.
A red Nissan Micra is seen driving at speed down a steep hill in a field, then leaping through a raised gap in a ditch, over the public road, and passing through a gap in trees across the road before landing in another field and driving off.
A person standing close to the ditch appears to be keeping watch and jumps out of the way as the car approaches its take-off position.
Onlookers can be heard laughing and calling for the stunt to be repeated.
There are fears the car jumped over a section of the N71 — one of the busiest tourist routes in the region.
Several people have posted comments describing those involved as “legends”.
One comment states: “That’s just the funniest thing I’ve seen in a long time! Class!”
The clip has been viewed more than 8,600 times.
RSA spokesman Brian Farrell described the stunt as “dangerous and highly irresponsible”.
“Those involved put their own lives, and the lives of other road users at risk,” he said. “This type of behaviour cannot be condoned. Anyone who comes across this kind of behaviour should report it to gardaí immediately.”
Clonakilty-based Garda Superintendent Pat Maher said this particular incident is not the subject of a current Garda investigation, but he said he would be very concerned about such activity. “I would appeal to the public who may be of assistance to us to give us any information they have, in confidence, in order to stamp out this kind of behaviour to prevent possible death. This can only end in tragedy.”
He urged people to contact Clonakilty Garda Station on 023-882 1570 or the Garda Confidential Line on 1800-666 111.
Meanwhile, following a Garda investigation into the Nenagh footage, three men have been questioned and two cars have been seized.