'Believe' - One of the first words rescuers shouted to the boys stuck in the cave, as ITV News Correspondent Rebecca Barry reports
Footage of the moment rescuers told 12 Thai youth footballers and their coach trapped in a cave to "believe" has been released as a part of a new documentary.
Expert British cave divers John Volanthen and Rick Stanton led the rescue effort and have now told ITV News about the mammoth effort.
Mr Stanton said: "You really couldn't see your hand there so we were doing it by feel or dead reckoning and judgement.
"Not knowing what you're going to encounter, whether that's children's bodies, that definitely added pressure."
In the footage of first contact, the divers could be heard shouting "how many of you?" before repeating "believe" over and over again.
It took nine days to find the boys deep in the cave and Mr Volanthen said he was "couldn't believe" they were all alive.
The only way of extracting the children involved injecting them with ketamine, putting diving gear on them and escorting them underwater for two and a half hours.
Mr Volanthen said: "That responsibility of taking a child where if anything had happened to the mask that was keeping their face dry then the child would have unquestionably have drowned."
The operation was considered extremely dangerous at the time and a Thai Navy SEAL died while diving in the cave.