Rhys Murray died on the opening day of the In It Together festival in Margam, Port Talbot.

A spokesperson for festival organisers, Escape Records, said they were "deeply saddened" and said "[their] condolences go out to the boy's family at this time".

His brother Thomas paid tribute to him on social media and described him as "the most amazing person".

"My life will never be the same," he added.

"Very little people know how close we were, and when I say he was my world I mean he was my everything.

"I am truly heartbroken and I am praying for the day that I meet you again, my baby brother, sleep tight, I love you forever and always."

Afan Arts, a society which encourages young people to get involved with creative projects, of which Rhys was a member said they announced his death with "profound sadness and a heavy heart".

Rhys helped found the organisation's youth theatre and they said "his passion for performance shone".

"We send our love and support to Rhys' family, his friends, Ysgol Cwm Brombil and all those affected by his passing," they added in a statement.

"Afan Arts will use the healing power of the arts to support everyone, going forward, but for now we simply mourn his passing."

Ysgol Cwm Brombil school said that a pupil died on Friday following a "serious asthma attack which led to complications".

In a statement that did not name him, they said that he was a "wonderful young man".

"It is with deepest regret that on Friday, 26 May, one of our valued pupils tragically passed away following a serious asthma attack which led to complications," they said.

"Our most sincere condolences go out to the family and friends of this wonderful young man."

Chief Inspector Declan Cahill of South Wales Police said officers were called to the festival shortly after 8.30pm "after a 16-year-old boy from Port Talbot suffered a medical episode".

"Sadly, the boy died while being taken to hospital via ambulance. Our sympathies are with his family at this time."

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The forced added there were no suspicious circumstances and HM Coroner had been informed.