On Saturday, a youth soccer team and their coach entered a well-known cave in Chiang Rai, Thailand.
That was the last time anyone saw the team before they became trapped underground.
Now, rescue workers from three countries worry time is running out to save their lives.
Trapped by floodwater
The team of children, aged 11 to 16, and their 25-year-old coach left their belongings piled at the entrance to the Tham Luang Nang Non caves.
The caves are a popular tourist destination, but regularly flood between July and November.
Rescue workers believe that after the cave quickly flooded last weekend, the team became trapped somewhere in the six-mile underground network.
Five days after parents of the children reported them missing, British cave experts, Thai Navy divers, and a U.S. military team are working around-the-clock to save them.
More than 1,000 workers in all are crowded around the caves, with military helicopters and drones searching the area for hidden entrances.
"We won't give up. That's the key here."
So far, the rescuers have focused on pumping water out of the cave to drop the water level.
But more rain has interfered with their efforts, especially because water pumps had to be turned off during heavy showers to prevent an electrical accident.
Expert divers are searching for the children inside the cave, but say the water is as murky as "cafe latte."
Rushing water in the underground tunnels has also put the divers at risk.
Some corners of the cave are so sharp divers have to bend their bodies to get through.
In spite of the setbacks, deputy national police chief Wirachai Songmetta is optimistic that the boys can still be rescued.
"We won't give up," he said, "that's the key here."
Time is running out
The team, called the Wild Boars, are believed to be trapped by floodwater in a large, open chamber near the center of the caves.
Rescuers say that even if they aren't, there are plenty of dry places inside where the team can take shelter.
The cave is not too cold, and experts say the team can survive for weeks without food.
The biggest concern is that the group will try to swim out of the cave after underestimating the underground currents and injure themselves.
There are plans to drill new entrances into the caves from the surface, but the risk of causing a collapse means they won't be used right away.
While emergency teams are staying positive, worried parents of the missing children are camped outside the cave waiting to be reunited with them.
Let's pray that rescuers will bring the whole team out safely very soon!
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