Last Saturday, 12 young boys went to explore a cave with their coach after football practice in northern Thailand.
Their bikes were found abandoned at the entrance and shortly after, heavy rain sent torrents of water through the cave.
Over the past week, rescuers have been mounting an increasingly desperate search, in the hope the group are alive deep inside the cave but trapped by floodwaters.
Here's what the operation, in the jungle-covered hills around Chiang Rai, involves:
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