A teenage boy has suffered multiple fractures after falling 20ft into a quarry in south Wales.
Fire crews from three stations were dispatched
The 17-year-old was one of two boys discovered clinging to a quarry ledge by workers at the site in Pontypridd.
The boys were hanging by their arms with a 20ft drop beneath them at the Craig yr Hesg quarry near Berw Road.
Fire crews rushed to the scene at 1945 BST on Thursday but by the time they got to the location of the boys, one of them had lost his grip and fallen.
The boy is believed to have broken both thigh bones and one hip. He suffered chest injuries with possible broken ribs, head injuries and multiple lacerations to his hands.
Station Officer Steve Logan from South Wales Fire Service said that crews from Pontypridd, Newport and Barry were dispatched but only two appliances were needed.
"When we arrived we could see where the boys were hanging but in the minute it took to get to the scene, one had slipped and fallen onto rocky and uneven ground," he said.
"He was unconscious and had various injuries.
"His friend managed to get to safety by sliding down a rope we had dropped down for him.
"But as soon as he got to safety he ran off.
"They had obviously been messing around that's for sure, they were doing it for fun.
"We weren't able to ascertain if they had been climbing up or climbing down, but they were very lucky that they weren't killed," he said.
Ambulance crews and police also attended the scene and gave first aid to the teenager who was drifting in and out of consciousness.
"Quarries may look like an attractive place to hang around but they are dangerous places," said Mr Logan.
"When he fell, he landed on his feet and has suffered a number of injuries.
"He was a very lucky boy not to have been killed," he added.
He was taken by ambulance to the Royal Glamorgan Hospital where he was treated for several broken bones, lacerations and head injuries.
Police are investigating the circumstances surrounding the incident but do not believe anyone else was involved.