An eight-year-old boy was described as "very poorly" after being dragged from the water at a Keighley beauty spot by a fire fighter then airlifted to hospital.
The boy appeared to have sustained a head injury after entering the water at the Tinker Bridge water fall, North Beck, and is understood to have stopped breathing.
Emergency services were called by members of the public and the fire fighter went into the water to rescue the child.
Paramedics worked on him at the scene and, it is understood, were able to restart his heart before he was taken to Leeds General Infirmary by the Yorkshire Air Ambulance helicopter. He remained unconscious at that point.
The circumstances of how he was injured remain unclear, but according to police he was also very cold by the time emergency services arrived and they worked to warm him up.
The water depth at the waterfall is limited and it is believe he may have struck his head while swimming.
He is thought to live locally and his family were with him at the hospital, where the most recent condition check described his condition as very poorly.
The water fall is a beauty spot which is frequently used by swimmers and fun seekers who jump from the head of the waterfall into the pool below.
The incident comes after the hottest spell of the summer so far and safety organisations always warn against swimming in open water because of the risks involved.