Transcript for Race against time in desperate search for missing soccer team

Over seas now. It has been a week since a young soccer team disappeared in a system of caves in Thailand. An intense search now under way to find those boys, but rain is slowing down the rescue effort. ABC's foreign correspondent James Longman is at the scene with the latest. Reporter: One week since the 12 young soccer players and their coach went missing in these caves and the search is intensifying. Over a thousand forming an international rescue team. Among them U.S., British and Chinese specialists trying anything they can, drilling into the rock face, dropping maps and care packages through small crevices and using ultrasonic sensors for any sign of life. It's a colossal effort. This small patch transformed into a major operational center and it's right at the entrance to that cave. The team trapped along miles of passageways and tunnels that can flood up to 0 feet during recent heavy downpours. The hope is they found higher ground to escape the floods. They could survive for weeks if they have clean water. And meanwhile, an entire nation looks on in hope. This mother calling out, "My son, come out, I'm waiting for you here." The only thing remaining, the boys' bicycles left at the entrance before they went in for what should have been a fun excursion. Another entrance has been found but the issue is so much of these caves have never been explored so rescuers really not sure what they'll find although everyone here is staying hopeful. Guys. Yeah, fingers crossed across that country and this one. Yeah. It's amazing how they're putting the care packages down into the cave just hoping that they might stumble upon some of these goods and food and water to keep them surviving. And parents standing outside trying to yell to their kids hoping they can somehow hear them inside. Wrenching for those parents.

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