Lewis Haunch, from Leigh, in Greater Manchester, underwent emergency treatment in hospital but was pronounced dead shortly after midnight yesterday.
Police were first alerted by staff from the festival at around 4.45pm on Saturday, August 27.
The boy had been taken to St James’ Hospital in Leeds by ambulance in a critical condition.
Today police said they had finished their initial questioning of two 17-year-old boys arrested in the Greater Manchester area on suspicion of drugs offences.
They have been released on bail pending further enquiries.
Leeds Festival’s Police Commander, Chief Superintendent Keith Gilert, said: “Our thoughts are naturally with the family of the young man at this time. They were made aware of the incident by officers as soon as possible and were assisted to attend the hospital as quickly as possible. We will continue to support them through this difficult time.”
Investigations into Lewis’s death and how he got the drugs are ongoing.
Early enquiries have indicated that he took the drugs immediately before collapsing.
One festival-goer said she believed she saw the teenager as he was being treated by medics.
Hayley Briggs said: “It was right outside the guest area and the guy just looked in a very bad way.
“He was being cradled by one of the first aiders before the ambulance arrived.”
A report will be sent to the Coroner in due course, police said.
Mr Gilert added: “In partnership with the organisers, Festival Republic, we will continue to take action against those who risk the lives of others by supplying drugs.
“Anyone who has any concerns for either themselves or others at the Festival should contact Festival site or security staff or seek medical assistance.”
Festival Republic managing director Melvin Benn said: “The loss of this young man’s life at Leeds Festival is simply devastating and deeply sad for all those associated with the festival.
“We understand the police have taken action against those that may have supplied the drugs in Manchester, and we are working with them to assist in any way that we can.
“Medical teams on site responded incredibly quickly, and I’m certain we could not have done more to prevent this desperately sad loss of life.”
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