The long-running effort to save children in Thailand's Tham Luang Nang Non cave claimed its first victim on Friday, when a former Thai Navy SEALs member died of lack of oxygen.

The rescuer, identified as a 37-year-old Saman Gunan, was working as a volunteer, SEAL commander Arpakorn Yookongkaew told a news conference on Friday morning. Saman died while diving to place oxygen canisters along a potential route for the upcoming extraction attempt. However, he ran out of oxygen himself and lost consciousness while trying to return.

Why it was so difficult to extricate Thai cave boys Happy ending after harrowing ordeal After deliberating over how best to rescue the boys and their coach - considering even whether to teach them how to dive, or wait for the monsoon waters to recede months later - rescue workers finally settled on pumping out as much water as possible, sedating those trapped and strapping them to a diver who shepherded them to safety.

Why it was so difficult to extricate Thai cave boys Found alive after nine days Rescue divers initially found the 12 young soccer players and their coach alive on July 3 after they went missing in a Thai cave 10 days earlier. Fighting against time, rain and low oxygen levels, rescuers managed to free the first four boys successfully on July 8. The rescuers faced a complicated and dangerous diving mission to free the rest of the team and their coach.

Why it was so difficult to extricate Thai cave boys Glimpse of joy Families of the teenage soccer players expressed their joy over the discovery of the boys nine days after they went missing. Outside the cave, the mother of one of the boys said she was "glad" for a glimpse of her son. "He's thinner," she said, as she ran her finger over the image of her son on a television screen.

Why it was so difficult to extricate Thai cave boys Massive rescue efforts Thai rescuers were assisted by an international team comprising experts from China, Australia, the USA and Britain. A video from the Thai Navy SEAL Facebook page showed the group several kilometers inside the 10-kilometer (6-mile) cave network on a small wedge of dry ground. The boys moved 400 meters further in as the ledge had become covered by water.

Why it was so difficult to extricate Thai cave boys Trapped by flooding The boys, aged 11 to 16, and their 25-year-old coach entered the cave to celebrate one of the player's birthday. They became trapped in the cave, a local tourist spot where similar incidents have taken place in the past, when sudden rainfall flooded its entry on June 23. It was later reported that some of the boys could not swim, further complicating the rescue.

Why it was so difficult to extricate Thai cave boys A difficult mission The rescue mission proved difficult for divers whose efforts were continually hampered by rising water that filled sections of the cave, often forcing them to stop. Getting trained divers into the cave was easier than getting untrained kids out.

Why it was so difficult to extricate Thai cave boys Boys' safety paramount The entire nation was glued to the media coverage of the rescue mission, and Thai authorities insisted they will not compromise on the safety of the trapped group. Prime Minister Prayuth Chan-ocha (above, at right) thanked international experts who helped find the boys.

Why it was so difficult to extricate Thai cave boys First boys rescued The first four boys were rescued by a team of 13 foreign diving experts and Thai Navy SEALS, who helped them navigate the flooded cave tunnels. The head of the rescue operation said they were the healthiest in the group. The rest of the boys and their coach would be rescued from the cave over the next two days.

Why it was so difficult to extricate Thai cave boys Safe and sound Doctors who treated the boys after their rescue reported that while they had lost weight, the otherwise appeared to be in good health. The dozens of divers and hundreds of other rescue workers have been celebrated around the world as heroes, especially 38-year-old former Thai Navy SEAL Saman Kunan, who died after bringing the group supplies of air on July 5.



"We are trained to expect risks at anytime," Arpakorn said. "It's part of the job."

"But even though we have lost one man, we still have faith to carry out our work."

Time limited

The children remained trapped in the underground complex as authorities mull over ways to extract them. It takes divers 11 hours to get to where the boys are and back to the cave entrance.

The diver's death serves as a reminder of the risks that the boys face.

When asked how the children could be extracted safely, given that an ex-SEAL lost his life while attempting the journey, Arpakorn said the rescuers would take more precautions with children.

He also said there may be little choice but to effect a rescue due to the threat from flooding during the monsoon rains. "At first, we thought the children could stay for a long time ... but now things have changed, we have a limited time," Apakorn said.

Few of the boys are able to swim, and none of them have any diving experience.

Thailand's Navy SEALs boast close links, including joint elements of training, with the US Navy SEALs.

Watch video 00:40 Thailand: Window for cave rescue narrows

dj,jm/ng (dpa, AFP, AP)

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