Four boys among a group of 13 trapped in a flooded Thai cave for more than a fortnight were rescued on Sunday, authorities said, raising hopes elite divers would also quickly save the others.
The junior team comprised of 12 boys aged between 11 and 16 years while their coach, who was leading the expedition, is just 25-year-old.
Monsoon flooding cut off their escape route and prevented rescuers from finding them for nearly 10 days.
Though four boys have been rescued as of Sunday night, the mission to extract the rest could take two to four days depending on the conditions in the cave.
"Narongsak Osatanakorn, the head of the joint command centre coordinating the rescue, said Sunday morning was the most opportune time to launch the operation, citing the ideal weather, water and the kids' readiness, physical and mental". Mr Musk's companies had said they could help by trying to locate the boys' precise location using Space Exploration Technologies Corp. or Boring Co. technology, pumping water or providing heavy-duty battery packs known as Tesla Inc. Each of the boys will be accompanied by two divers.
The rescue operation began at 10am local time with the first child expected to emerge at 9pm.
Retrieving the boys from the muddy bank on which they took refuge requires a almost 11-hour round trip through 4 km of winding, submerged pathways, tunnels and fast-flowing, freezing water.
Officials did not clarify this morning whether the complex effort to dive the team out of the kilometres-long Tham Luang cave in northern Thailand had started. "They have not been moved to Chiang Rai hospital yet", Tossathep said.
"We're still at war with water and time", he told reporters.
Initial euphoria over finding the boys alive quickly turned into deep anxiety as rescuers struggled to find a way to get them out. It was not immediately known if a US diver was among them.
"Everyone who is not involved with the operations has to get out of the area immediately", police announced via loudspeaker at the site on Sunday morning, an Agence France-Presse report said.
Meanwhile, efforts are on to save the children from the caverns as rain water has filled the rescue route.
One of the boys, identified as Tun, wrote: "Mom and Dad, please don't worry, I am fine".