Duangphet Phromthep, one of the 12 boys rescued from a flooded Thai cave after a weekslong operation that drew global attention in 2018, has died in the U.K., British and Thai officials announced Wednesday.
Phromthep, who was enrolled in a soccer academy in Leicestershire, England, died after being rushed to hospital on Sunday, Leicestershire Police said in a statement to CNN.
The northern regional branch of the Thai government's public relations arm said on Facebook that Phromthep, 17, died due to an accident, without providing more details.
"The atmosphere at his house in Chiang Rai province was full of sorrow," PR Thailand's statement said.
Zico Foundation, a Thai non-profit organization which had helped Phromthep study in the UK via a soccer scholarship, wrote on Facebook Wednesday: "Zico Foundation would like to express our sorrow for the pass of Dom Duangpet Phromthep, a scholarship student from Zico foundation," posting a picture of Phromthep.
CNN has reached out to The Brooke House College Football Academy, where Phromthep was enrolled on a football scholarship. The Academy said it would be releasing a statement.
A daring rescue
Phromthep was the captain of the Wild Boars youth soccer team which was rescued after being trapped for more than two weeks in a flooded cave network in the northern Thai province of Chiang Rai in the summer of 2018.
The 12 boys and their coach became trapped when rising flood water cut them off deep inside the cave, sparking what became a near three-week international rescue effort.
Divers involved in the rescue described treacherous conditions, with fast-moving shallow water passing through very narrow passages.
In a complicated three-day final operation, the boys were split into groups of four and provided with 5-millimeter-thick wetsuits, full face mask breathing apparatus and air bottles.
Each boy was taken out by two divers, who carried their oxygen tanks and guided them through murky tunnels. Each rescue took several hours, with much of the time spent under water.
The most dangerous part was the first kilometer, during which the divers and boys are required to squeeze through a narrow, flooded channel.
Rescuers needed to hold the boys' oxygen tanks in front of them and swim pencil-like through submerged holes. Having completed this section, the boys were then handed over to separate, specialist rescue teams, who helped assist them through the remainder of the cave, much of which they could wade through.
Phromthep, known as Dom, left the cave as part of the second group of boys carried out on more than two weeks after they were first trapped. He was one of three boys whose birthdays slipped by while they were deep underground. In his first message to his parents he implored them not to forget. "I'm fine, but the weather is quite cold. But don't worry," he said. "Don't forget my birthday," he said.
From hospital, after his rescue, he said he wanted pork and rice to eat and thanked everyone for all their support.
All 12 of the rescued boys and their coach were then transported to a nearby hospital for recuperation.
Family members greeted the news of their rescue with relief and tears of happiness, punching the air when they heard that their boys were alive.
Reacting to Phromthep's death, Prajak Sutham, one of the Thai cave survivors, wrote on Facebook: "We have been through together a lot, good and bad times. We had went through life and death situations together, when you told me to wait and see the time you became a national player. I always believed that you could do it. Last time we met before you left to UK, I jokingly told you that, when you're back I would ask for your signature. Rest in Peace Bro, we always have each other, the 13 of us."
The Doi Wao temple in his hometown in Chiang Rai also expressed their condolences to Phromthep's mother.