Authorities have said helicopters were ready to take cave evacuees to a hospital.
Rescued schoolboys are moved from a military helicopter to an awaiting ambulance at a military airport in Chiang Rai, Thailand, July 9, 2018.
Now only five members of the team remain in the cavern complex, where they became trapped more than two weeks ago.
8 out of the 13 boys of the Thai junior football team were rescued from the flooded Tham Luang cave in Thailand.
"The fact that it took so many hours underscores how precarious this whole mission is", she said.
Friday, June 29: Thailand's junta leader Prayut Chan-O-Cha visits the site, leads a meditation and jokes and cooks with relatives, asking them not to give up hope.
"We have to place new oxygen tanks (along the route) as the previous ones have been used in today's operation", he noted. The search and rescue operation has involved dozens of worldwide experts and rescuers, including a USA military team.
The water in the cave is muddy and unclear, with one diver comparing it to a cafe latte.
Four of the 12 boys were extracted from the Tham Luang cave network in the Chiang Rai province Sunday evening, before the operation was suspended overnight to allow oxygen tanks to be refilled before rescue teams begin the next phase. Officials did not immediately comment.
The extraction of those remaining is expected to take another two to four days, depending on conditions.
Eight boys and the coach remain trapped, and the ordeal has been a closely watched news story around the globe.
A major concern of the rescuers is that oxygen levels in their safe space could fall dangerously low.
Rescuers are racing to beat the next downpour, which could further complicate efforts to remove the boys, aged 11 to 16, and their 25-year-old coach.
Thailand's Meteorological Department said there was a 60 percent chance of rain Monday with thunderstorms forecast throughout the week. Narongsak said the healthiest have been taken out first, and the next phase of the operation would start in 10-20 hours. Musk said based on "feedback from Thailand", the engineers chose to build a "tiny, kid-size submarine" using a large silver tube meant to be affixed to a SpaceX Falcon 9 rocket.
Videos showed Musk's team testing the metallic pod in an LA-area high school swimming pool.
It's a total of four kilometers from the entrance to where the boys are trapped.
According to our correspondent, Thai officials have warned the rescue could take three or four days in the worst case scenario.
Sam Teller, spokesman for Boring Co., said Sunday that the company has four engineers who are "offering support in any way the government deems useful".
Authorities temporarily stopped their efforts Monday to replenish air tanks along the cave's treacherous exit route.
Expert divers managed to get four of the 12 boys to safety on Sunday.
Shortly after, ambulances were seen racing towards the nearby city of Chiang Rai down roads that had been cleared of traffic to smooth the journey.
Doctors are monitoring them for any illnesses they may have picked up in the cave, and supervising efforts to build up their strength after more than two weeks with little food and no natural light.
Pixley said water rescuers use thermal suits to protect themselves from hypothermia.