Thai cave rescuers describe mission, say they expected some kids to die

Divers raced against time, battled low visibility and near-impossible conditions to rescue 12 boys and their coach from a cave in Thailand.
9:18 | 07/28/18

Coming up in the next {{countdown}} {{countdownlbl}}

Coming up next:



Skip to this video now

Now Playing:


Related Extras
Related Videos
Video Transcript
Transcript for Thai cave rescuers describe mission, say they expected some kids to die
Reporter: Under a monsoon-soaked mount I northern Thailand, in these down dark, atic death trap. After nine days ofperate searching, the mission members ofss soccer team and theiroa are miraculously alive How man of you? . 13? Yes. Brilliant. Absol elatio followed very quickly with, wait a sec, nowe've gt these kids out. Reporte tonight T heart-racing details we didn't knowbout the re until now. Dily from the divers who carriethe divers W th boys, John velantin and ric Stanton, D few divers Jason and S Jewell, belong to anitish caving team with unique rescue stem-cell skills. In Thai Tse voluee working without pay, come to be kn awesome foursom I'd never have a send about whether I would go. I think ium nature to know if you've got an ability, then of course what standsween aalf underground obs crs of rock chrs, half-flood canals, fully suerged sections. The longest ofhosef 0 meters, the length seven olympic swimmin pools, filled water so muddy it's like swimming in coffee. We always knew we could get them out, get out alive or not. Reporter: A U.S. Air force search and rescue team, headed upyajor crles hodges, and sterergeant Derek Anderson, joins theef what was the probability of success? When I was asked T question bhe governor,hat told him is, I think we can probab realistically save 60% to70% of the kids. I expect any fromhree to five to die in this Tralator: Today is d-day. We are 100% ready. Enoous cache of extra air cre already in place and support divers Ed thrghcave. The tip of the elite foursome of British vers. It diver, one boy? That's correcs. That's a tremendous amount of reonsibility. Yeah, very much so. The find the boysckingly. Ade madey all boys,ecause R physicalnd mental conditn was about the same. Th boys livedt from ticycle H to tell their parents thenews. Reporte choosing who was first in line is actual small sion. That boy will be at of human Guinea pig iirstf I kindrescue. And I falls to mallenson to shherd the boysut safely. Ite ou volunteered? I'm not one to at the back, I'm usually a the front. I just vollready weang a we, the cld walks down a steep slope into T water. Now it's Tim F an absolutely critic EP, aeed T in advance byhe Thai government. Th injecte with a commonly used said called K kettamine byn Australian doctor and anesthesiologist. Hehot I not to relax the boy,s to knock him out cold. I can't have him twitching around. When thetartving, the arms moving there's potent for them T kill themselves therwas potential fhem to kill us. Reporter: Soont F boy is out cold. And a fma is Strapp tiy sgle leak could ntiallfatal. I was not fully confide of hem out E. We didn't know at first how they wereeact ie water, whether the drug we'd gi them WOU beufficient to keep them under F oo enson is E turning back. Hecold mky with the boy for THA daunting first dive stage. Remember,s eters long. 3 1/2 ball field what follo next is a sort of choreographed underwaterbaet, hand maenson has to vest as he floatscedown. Liken I T underwater obacle course. In which you're blind? In which you'rend and N't rememr the obstacles on the way in. Repid about 20 past agoni minutes, mallson success completesge. Waiting for hre two support dive hoarse help him G the un boy out of the water. Realized at, . The D Ed. Get divers have thysicallyarry the child to the nextpoint,henm across deep canals wit rushing water. It was tually harder in the canal sections. Because we WER under water, he was neutr and I was neutral, it's hard to swim in the canal and push a inert chd along W you. Reporter: S halfway H a strughosels when a tential strophe haens. Swimming down a canal in started coming of you'v got It wa very tricky. I had syringe fg on the surface trying to grab all O them. You literally grab the stuff in the water, trying to putt back in? G your syringes back in and too. Reporr:er whateemed an mallensonrges om the darkness with that first C in tow. Are you ? The kid's breathing? Id doing phone. Repng boy immedi TD to by medics. Ranslator: The doctorld measure thexygen lev I the body, the kid'sbreathing, and the puls Ror then loaded onto a stretcher for the remain half-mile extra. Ranslator: It took more than 100 peopo bring to th entrance of cave. Reporter: After 16 T rst boy finally out. He immediately rushed into a waiting ambulance. Everyone was -- Bigre re S. You're ke is this going to happen a sec time, is this going to happen third me? I reallyet the bad ne. Ths like, child three's up, hereathing, 'S Translator: The third and the fourth came out at 7:40 and . Today was very successful. Reporter: By nightfall, the neay more boys trade the dark of the cave for a star lit night. Minutes ago we the seventh and eighth ambuls thmost precious cargo -- Reporter: But this is not a il sleeping inside theave th The pressure was really on. Thexpectationas W WOU get them allout. Reporfter pullinghe soccer coach through the mt das part of the cave's flooded section, in resc mallenson hands him off to anoth diver and back to to grab theast boy, a 13-year-old nicknamed mark. He's a really small Reporte mason encounters what could be aatal flaw. Mark is too small for the diving sk brought for him. There was aap under his chin. We couldn't get it to seal. Reporter: Remember, a leaking seal means the boyould drown so with the clock ticking and the final child alreadysedated, th D use a different's not either. It might fm a tight seal around the boy'sface. We knew we didn't have more time. We knew this wash L option. Reptemallenson is now laser-focusedn keeping that mask on the boy' ce. I developed a technique where I'd pul him iea tight with down re, and I'd extend my head over thetop ofhis. So my hit Theall first and sort of protect his head. H M dk you hit your head that dozens. Reportemallenson, slow going withmark, emges. It's the end of the18-day drama thattivated theworld. Fromhe beds, the boys and their C Now I'mer I'm Ver thank you so carefully -- thank you so There wereer people on that scue, I they ou ny S.A.S that went into the chamber a Syed th them to the Hink they're a bter classifition ofroes. Happy. The people of the world are happy. So I consider this opera th the world will never forget.

This transcript has been automatically generated and may not be 100% accurate.

{"duration":"9:18","description":"Divers raced against time, battled low visibility and near-impossible conditions to rescue 12 boys and their coach from a cave in Thailand.","mediaType":"default","section":"ABCNews/Nightline","id":"56883632","title":"Thai cave rescuers describe mission, say they expected some kids to die ","url":"/Nightline/video/thai-cave-rescuers-describe-mission-expected-kids-die-56883632"}