Chiang Rai provincial Gov. Narongsak Osatanakorn, speaking as the second day of the rescue mission got underway, predicted that all 12 of the boys on the soccer team and the coach will be safely brought out of the labyrinth where they went missing 17 days ago.
"I insist that all 13 will be safe and sound," Osatanakorn said.
Rescuers are hustling to bring the Wild Boar soccer team members out of the Tham Luang Nang Non cave before heavy monsoon rains forecast for the area strike, which could flood the cave again.
"We thank the God of the rain. Asked for there not to be rain," Osatanakorn said at a news conference Monday.
After the first four boys were brought out of the cave to safety Sunday, rescuers had planned to take a 10- to 20-hour pause to replenish the cave holding the remaining boys with oxygen and give the team of 18 divers who have been leading the boys on a perilous journey to safety a chance to rest.
However, the rescue effort resumed a few hours earlier than planned on Monday, and about six hours after it started, divers emerged with the fifth rescued boy in tow about 5 p.m. local time.
Over the next three hours, they brought out three other boys, a source close to the operation told ABC News.
The Thai Navy SEALs confirmed on their Facebook page on Monday that eight members of the Wild Boar soccer team had been rescued.
"Hooyah," the SEALs Facebook post reads.
Osatanakorn said Monday's mission lasted nine hours, about two hours less than the rescue operation Sunday.
He described the four boys rescued Monday as "safe and sound" after they made a treacherous trek out of the bowels of the cave in "buddy teams" escorted by elite divers through narrow crevices and floodwaters that required the use of scuba gear.
After the retrieval of the boys Monday, Osatanakorn said the rescue mission in on pause again for about 20 hours to replenish the cave with oxygen pumped in from the outside and to allow divers to rest.
He said the third and possibly final leg of the rescue mission for the remaining four boys and their coach will commence on Tuesday.
Most of the divers who saved the boys Monday are part of the same crew that fetched the first four boys from the cave Sunday.
The four children brought out of the cave Monday, who were not named, were put in ambulances, driven to waiting helicopters, whisked off to an old airport in Chiang Rai, and then transported again by ambulance to a hospital where their four teammates rescued on Sunday are being treated.
Officials on Sunday said the four boys rescued that day were "hungry, but happy," and eager to eat khao pad ka pow (fried rice with basil).
As of Monday, the eight rescued boys have been quarantined at the hospital in case of an infection. Officials said they were considering allowing the parents to see the boys through a glass partition.
The mission to save the boys has captured the attention of the world and drawn international search-and-rescue crews from the U.S. military, China, the United Kingdom, Australia, and Japan.
The 12 boys and their 25-year-old coach became trapped in the underground maze on June 23 after they entered and their exit was cut off by flash flooding.
The recovery mission was begun in earnest on Sunday due to favorable weather conditions. Approaching monsoons that have been forecast to inundate the area for days have held off, allowing rescuers to pump floodwaters from the cave to make the journey out quicker.
The first rescued boy was brought out of the cave at 5:40 p.m. local time on Sunday, followed 10 to 20 minutes later by the second boy, Osatanakorn said. About two hours later, the third and fourth boys were pulled from the cave 10 minutes apart, he said.
"Today was very successful, more than expected," Osatanakorn said Sunday.
Officials said Monday that despite rain Monday morning, the weather was holding out.
"A lot of people were afraid if it were to rain a lot," Osatanakorn said. "The weather is good now, but cloudy."