A man was pulled from the sea unconscious after jumping from a cliff into the water, police said.
Officers from Dyfed-Powys are warning about the dangers of tombstoning – jumping into water from a height – after the incident in Tenby.
The emergency services were called to a beach opposite St Catherine’s Island at around 6.15pm on Saturday and the RNLI administered CPR to the 23-year-old who was unconscious and not breathing.
Inspector Gavin Howells said the RNLI “most likely saved this man’s life”.
He said: “This incident highlights the serious danger posed by tombstoning or cliff jumping, and the potentially life-threatening consequences.
“We urge people not to take part in this sort of activity anywhere along our coastline, and not to put themselves or the emergency services at risk for a thrill.”
The man regained consciousness and was taken to hospital for assessment.