A teenage boy is in critical condition after he was pulled unconscious from the River Thames near Hampton Court by members of the public.

The teenager was air-lifted to The Royal London Hospital in Whitechapel in the early hours of Wednesday evening (June 21)

Docked in the moorings opposite the palace, a boatsman saw the catastrophe unfold moments after the teenager had dived into the water and not re-surfaced.

The witness said: “It was about 6.30pm and we heard lots of kids shouting but we thought they were just messing around diving into the river but then someone was knocking on my boat asking for my dingy.

“There looked like there were about six or seven members of the public treading water and diving down looking for the boy who hadn’t resurfaced after diving in and I swear they were doing it for about 15 minutes.”

“They managed to find the boy’s body eventually and took him to the bank and began to perform CPR on him.”

He added: “I think the boy’s friend must have called 999 because the police showed up first and then the fire brigade but on the wrong side of the river – they had to use my dingy to get across.”

It is believed that the boy's pulse was found at the scene before the boy was air-lifted to hospital where the police have confirmed he is still in critical care.

“It is absolutely horrible but I am not a strong swimmer and so there was nothing I could do but I just didn’t sleep at all last night and those poor people who were looking for him – they deserve a medal.”

More than one lifeboat was at the scene but the case is being treated as 'non-suspicious' and further investigations are being carried out.

Hampton Court Palace has been contacted for comment.