Gardaí in Rathcoole are investigating after a convoy of horse sulkys were recorded racing down a Dublin road.
A video has been posted on social media of the race which is believed to have taken place over the weekend.
Cars, vans and horse and carts can be seen taking up four lanes of the N7 near Citywest.
The ISPCA has said it is "shocked and appalled" at the footage.
"Driving young horses and ponies flat out at excessive speed on Ireland’s busy roads, often by children as young as 10 years old, is an accident waiting to happen," said ISPCA Chief Executive Dr Andrew Kelly.
"All it takes is a trip or stumble which can be fatal for horse and sulky driver. It is also a risk for other road users and another serious accident or fatality is inevitable."
Dr Kelly said that action should be taken to take sulkies off public roads.
"We have seen far too often horses seriously injured or killed and left at the side of the road.
"These equines are often far too young to use for this purpose, causing serious damage to their undeveloped joints and ligaments.
"The most common injuries we see are broken knees, swollen joints, and neck injuries caused by badly fitted tack."