An RAF helicopter took the teenager to hospital, where he later died.
A 17-year-old boy and two teenage girls he died trying to save in the sea off Whitby were on an outing from a secure psychiatric unit, it has emerged.
The group were rescued after being swept out to sea on an inflatable dinghy off Whitby beach on Wednesday.
The boy died at Scarborough Hospital. The girls were treated and discharged.
Northumberland, Tyne and Wear NHS Trust said they were patients at St Nicholas Hospital in Gosforth – a medium secure psychiatric forensic unit for youths.
The unit cares for 14 to 17-year-olds who have either come into contact with the law as a result of their mental health issues, or are a risk to themselves or others.
Lifeboatman Hugh Ramsden said he tried to save the teenager
It is understood the teenagers in Whitby were being supervised by a group of adults from the unit.
A trust spokesman said: “We are all shocked and devastated by the news.
“We would like to offer our sincerest condolences to the family, friends and his fellow patients at this difficult time.
“We are fully co-operating with North Yorkshire Police to assist them in their investigation.”
The RNLI said the three had been using the dinghy close to Whitby’s West Pier.
They said it was thought the boy had managed to pull himself to safety using the ladder on the pier wall, but had returned to the water to help his companions.
Lifeboatman Hugh Ramsden said they tried to resuscitate the boy after recovering him from the water.
He said: “He was brought back to the Whitby lifeboat house and our coxswain took over CPR… until the emergency services arrived.”
Philip Rooks, who was at the beach with his children, said he was walking along the pier when his group noticed the teenagers were in difficulty.
The RAF helicopter flew the boy to hospital before returning to airlift the girls. Pic: Helen Barker He said they watched the boy swim to one of the girls who “was in real distress, shouting that she couldn’t swim”.
He added: “The poor lad managed to stay with her for a short time but after a couple of waves washed over him he turned in the water face down.
“At this point two lifeguards were swimming out against what I can only imagine being a strong current.
“Everyone started to shout to the young girl to turn her friend but you could see that she was struggling to survive herself.”
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