CHIANG RAI - Rescuers on Tuesday (July 10) successfully extracted all the remaining boys and their coach from a flooded cave in northern Thailand, after two successful operations on Sunday and Monday freed eight other boys in a saga that has gripped the world.

The rescued boys and their coach were carried out of the cave on a stretcher, as were the eight boys previously freed.

Shortly after the last person was rescued, the Thai Navy Seals posted on their Facebook page: "We are not sure if this is a miracle, a science, or what. All the thirteen Wild Boars are now out of the cave."

"Waiting to get the Thai Navy Seal who went to live with 4 other friends. Send some encouragement to them," they added in a separate post, referring to Thai Navy Seals, a doctor and other rescuers who had volunteered to stay with the boys as they awaited rescue.

Nineteen divers went into the Tham Luang cave near the Thai-Myanmar border at 10.09am (11.09am Singapore time) to begin what was expected to be an hours-long mission to rescue the five, who have been stranded for the past 17 days.

"We plan to bring out four boys and the coach," rescue chief Narongsak Osotthanakorn said ahead of the operation, adding that "a doctor, and three (Thai Navy) Seals" who have stayed with the group since they were found more than a week ago huddled on a muddy ledge will also leave the cave on Tuesday.

The Thai Navy Seals, who have been central to the massive multinational rescue operation, posted on its Facebook wall: "Today is 10 July 2018. It will be longer than previous ones. We will celebrate together finally. Hooyah!"

In each of the rescue missions on Sunday and Monday, four boys were led by expert divers through some 5km, including narrow, flooded chambers, to safety within nine hours. The eight boys, aged between 12 and 16, were whisked to Chiang Rai hospital and are receiving treatment.

Torrential rain struck the cave site on Monday evening and the downpour continued through Tuesday morning, but the authorities said preparations for the final rescue mission were unaffected.

"Today (Tuesday) we hope to be faster," Mr Narongsak said of the dangerous, complex rescue mission.

Rescued boys ask for chocolate bread

Doctors earlier on Tuesday gave the eight rescued boys a clean bill of health, saying they have no fever or serious ailments.

Dr Jesada Chokedamrongsuk, Thailand's health ministry permanent secretary, said at a press conference on Tuesday that "everyone is in a good mental state".

"At this moment, (there are) no worrisome conditions, everyone is safe," said Dr Jesada. Two of the boys had suspected lung infections but the four boys from the first group rescued were well enough to walk around their beds.

"The kids are footballers, are strong and have high immunity," Dr Jesada said, when asked why they have survived so long.

The boys had a good appetite but were mainly being given bland, easily digestible foods. However, doctors later relented after some of the boys asked for bread with chocolate topping.

They are still being quarantined from their parents because of the risk of infection and would likely be kept in hospital for a week to undergo tests, officials said.

Longer time expected for mission to bring out final 5

On Sunday, it took 11 hours to bring out four people. A second rescue operation by the same team of divers took only nine hours to bring out the next four.

"We spent two hours less today because we have more men. They are also more experienced," said Mr Narongsak, following the second rescue operation on Monday.

Given that Tuesday's operation seeks to evacuate more people, it could take longer than the first and second operations.

"We are confident that the next operation will be better and should be 100 per cent successful," said Mr Narongsak after the second operation brought four boys to safety on Monday.

He said that the health of five people still trapped inside the cave was "still good".

The 12 boys, aged between 11 and 16, went missing with their 25-year-old coach after entering the Tham Luang cave on June 23. Flash floods stranded them deep in the 10km-long cave complex.

Mountainside creeks have also been diverted, in the hope of limiting water run-off into the cave where the boys have been trapped.

The round-the-clock drainage of water from the cave and lower-than-usual rainfall during this period have sent water levels inside Tham Luang cave to the lowest in days, rendering most parts of a 5km escape route "walkable" and offering the boys a good chance of getting out safely.

During the rescue operations, each boy was escorted by two adult expert divers who helped him navigate his way - along guide ropes already put in place by rescuers - out of dark, narrow passageways inside the Tham Luang cave complex.

During Sunday's operation, the boys were under water for a total of 1km of submerged parts, said Mr Narongsak.

"The boys were wearing full-face masks and were able to breathe normally during the operation," he added.

The same team of 18 divers were deployed on Sunday and Monday, working alongside hundreds of other personnel at the scene who delivered and installed supplies and acted as back-up. One more diver was deployed in Tuesday's operation.

The Royal College of Psychiatrists of Thailand has offered guidelines for treating the 13 footballers once they are all rescued from the Chiang Rai cave, reported the Nation newspaper.

Psychiatrist Ananya Sinrachatanant wrote in a piece for the royal college that the footballers should first be shielded from critical and sensational news and commentary.

They should not be repeatedly asked to recount their personal experiences, as that would force them to relive their traumatic experience over and over again, she said.

When the rescued footballers are ready to talk about what they went through, it should be handled as lessons in survival and avoiding disaster in future, she added.