Transcript for Rescuers pull the first boys out of the Thai cave: Part 5

Reporter: Day 16. The beauty serenityf northern Thailand masks the drama about to pla out in Mae S as moms and dads pray for the safe return of their children mother nature and father time are forcing the hand of the Thai government Thosevy rains that are hehis way ceainly added nccause times running out. Repor with the threat rain running high and oxygen in the cave running low, CI decide they can wait no longer. It's "Go time." Translator: Today is d-day. We are 100% ready. Reporter: Ambulances are pooned near the cave helicopters are also ready to take the boys to hpital. And the hospitalelf is prep for the wst. You can see the stretchers lined out. Thcurity told us is these are for the boys rescued fr the , and insi you can see the guards on the eighth floor, it's dedicated entire thoids and reunitinem with their parents. Reporter: Over the weekend, E water VEL in the cave dropped 30%. Giving the international team of picked divers their shot to extract players and the coach from the clutches of this cave. So T amount of time boys D to stay underwater was at a nimum and that was when they felt like the time was right to strike. There are still huge ers, it's stin incredib icult operon. And I think we have to accept, it could go wrong. Reportehe long tr to E heart ofhe cave will be dangerous and strenuous. This is like climbiverest as far as diving is concd. Even among all the cave divers in the world, this is not the kind of task thaulreally be undtaken by the majority of them. Reporter: It will also be dark, veryk. Go in your ar and turn the lights out and that's what it's like. Reporter: 10:00 local time the first group of 18 divers enter the cave some head ctly for the boys location. T's no playbook his there's no protocol list for this Brithem out by diving isbably the St difficult and perilous operation. Reportend remember, mos of these boys do nnow how to .to combat nerves, according to Thai officials, the students were given an anti anxiety medication pre dive. The rescue divers have to get there. Get them ready kit T get them the right frame of mind and them bring them out. Reporter: Step the divers suit the first boy up with a full facemask W suit. If they lose them and cannot regain them, again, yoot a minutes to deal with that problem. The riskiest part of the dive begins immediate the trio dives down looking for a small hole twill lead them awrom pattaya beach "Buddy teams" are used with the lead diver carrying an ext taai a second diver assists and at times, physically hauls the boy through the water. They wanted to maurthat ese boys who have basically no dive experie some of them T even swi didn't have to do anything but breathe. Reporter: Som the clear ao tight ai tanks have to be removed in order to squeeze through. Rule number E, stay calm. Theulc and star thraarnd, trying to get out. And in doing that they could danger notnly themsees but the person who is trying toe that. They could dislodge their own face mask, they couetd somewh there's all sorts of things go wrong, they'd totally alien environment scared out of their wits, you know, worried to death. It would be incrleo expect them to dot wut panicking. We just sat there waiting.idn't know when it would happen, if it D ha, if it would go well, D there was this real silencethe jungle while we were waiting. Repr: It takehours for the teams to the slow passagto safety T at 5:40 P.M. Success, as the first boy emerges from thee. That is the first ambulance. The whole D has been wait to see this. The E country. Believe that the first boys from that cave are in that ambue. I'd been he days waiting for these kids to come out and we had thought were dead. We thought they were dead, and then they were coming out, one by one in ambulances, it W just extdinary to be there. Reporter:y for re how many kids can be rescued in one day. But just two hours L, is morgood news. The third and the fourth came out ab7:40 pm and . Today was verycessful, more than we expected. Reporter: R one of the so-called "War against water" goes to the ue team. Translator: The next rescue operation will take place within the next 10 to 20 hours. Befoy N do that,hey have to replenish the cave with oxygen Reporter: Next morning - the signal is given to launch the rescue again the rescue divers, now more adept at maneuvering through the Na passageways aing er time reaching the boys.and by latafternoon O more boys are brought to safety. I think scperation began on that first day, and the second day they had a tightly-moving, weil machine and holly the third day the same will be true. At a nearby school. Classmates are all smileon learnihe progress made on day two.si the youngoccer players te the same Hool here. Day 18, the third and final rescue D the final four soccer players and one coach are GHT to safety. Juster those final four boys andir coach were rescued from the cave, the water puhich had beenning water out suddenly failed and th Navy S.E.A.L.S had been pug out their equment from chrthree, and started to see that the water rising. Then it started fil chamber number two andmber number one. Had this Happe any earlier, it wouldben absolute disaster for the rescue. Theldren not being able to seeheir parents yet, under quarantine. Are medically needing to still be evaluated and make sure that they are checked out just fine before they are reunited witheir families. You never wan T see anybody brought out in an ambulance, much less young boys, but this was a moment of pure jubion his country. People wereling ag people were looking you ie eye. People were saying helloo you in English I stopped one woman and I ask her, you know, what is the change? E said, now we K T survived, so now we can smile again. Reporter: When we rn,

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