Army General Chalonhchai Chaiyakam said the efforts to rescue all 12 boys and their coach could last two to four days, depending on water levels and weather conditions.
"We are talking about it all the time", said Napattra Chokumpompan, 21, who works at a hotel in Mae Si.
Finnish volunteer diver Mikko Paasi, a long-term resident of Thailand, said the death of the Thai Navy SEAL had changed the mood on the ground and made real for rescuers just how unsafe the mission had become.
Rescuers at a Thai cave where eight boys and their soccer coach remain trapped have awoken to cloudy skies, after a night in which heavy monsoon rain lashed the mountainous region for several hours. Doctors and nurses at a triage camp set up just inside the mouth of the cave gave the boys quick physicals before they were sent to a hospital in Chiang Rai.
"They insist they are ready to come out", Narongsak said Sunday of the rescue team.
Four boys have so far completed the hazardous escape, according to rescue officials, and are receiving medical treatment.
It was reported that heavy rain was falling at the media centre, around a mile from the cave entrance, which could scupper plans to get the boys out today.
Mr Ekapol Chanthawong, his assistant, was to take the younger boys to a soccer field nestled by the Doi Nang Non mountain range, a formation with numerous waterfalls and caves that straddles the Thai-Myanmar border.
The team of 12 boys and their coach entered the cave system on June 23, but torrential rain caused the water level within the cave to rise rapidly, forcing them to venture deeper. Authorities placed plastic sheets around the approach to the cave, suggesting a rescue might be imminent.
Varner, Kraft lead at Greenbrier
Kraft fired a 6-under-par 64 on Thursday and wasn't done as he rolled up eight birdies against the bogey on No. 12 on Friday. Kim had back-to-back bogeys on the front nine on the Old White TPC, and then ran off five birdies over a seven-hole stretch.
Up to 18 divers are taking part in the rescue mission, which could take two to four days, officials said.
Reporting from Chiang Rai, Al Jazeera's Scott Heidler said it had started raining again on Sunday.
The video also showed a Caucasian diver walking heavily up a muddy slope carrying a face mask and a small oxygen tank, wearing a backpack with his flippers dangling behind his legs.
"The operation went much better than expected", said Chiang Rai acting governor Narongsak Osatanakorn, who is overseeing the mission.
The boys were discovered by British divers Richard Stanton and John Volanthen on Monday.
On Saturday morning, the Thai Navy posted photos of letters the group had written to their family and the outside world.
The death Friday of a former Thai navy SEAL, Saman Gunan, underscored the risks. Musk said based on "feedback from Thailand", the engineers made a decision to build a "tiny, kid-size submarine" using a large silver tube meant to be affixed to a SpaceX Falcon 9 rocket.
Some of the boys' parents told Reuters they had not been told who had been rescued and that they were not allowed to visit the hospital.
Engineers from SpaceX and The Boring Company are in Thailand assisting the government's rescue mission.
One of the boys, identified as Tun, wrote: "Mom and Dad, please don't worry, I am fine". I'm happy being here inside, the navy SEALS have taken good care. He has also thanked worldwide experts who helped find the boys.