Tham Luang cave is one of Thailand's longest, winding 10 kilometers (6 miles) and is also one of the toughest to navigate - especially in the wet months.
"Many people are coming", one of the divers told the group.
Having been underground for so long, it appears that the group were confused as to what day it was.
Divers John Volanthen and Richard William Stanton and caving expert Robert Charles Harper - all part of the British Cave Rescue Council - arrived in Chiang Rai last week, three days after the 13 went missing. They have been given energy gels to sustain them while a plan is worked out to bring them to safety.
Options like teaching the boys to dive, and swim with special breathing masks are being considered. But experts have questioned whether they will have the strength or ability to pick up the skills required in time.
While efforts to pump out floodwaters are continuing, it's clear that some areas of the sprawling cavern can not be drained, said Interior Minister Anupong Paojinda, a member of Thailand's ruling military junta. Diving gear will be used. Thailand's monsoon season has just begun, and with every storm that hits Chiang Rai, the water inside the cave continues to rise.
He said officials had met and agreed on the need to "ensure 100 percent safety for the boys when we bring them out".
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Gov. Narongsak had said earlier that the passageway goes upward in some places and downward in others and is extremely narrow, making it hard for divers and their gear to fit through. "If the gear is lost at any moment, it can be unsafe to life".
Chiang Rai Governor Narongsak Osatanakorn announced the development, stating "We found them safe".
Six AFP dive officers are assisting the Thai-led rescue operation, where priorities are getting food and first aid to the 13 and preparing to evacuate them safely.
The boys and their coach are not in danger of drowning.
Huge pipes spew water down the sides of the road and into the banana fields, trying to dry the place out as Thai authorities and rescuers from around the world scramble to rescue the 12 boys and their coach. "Maybe some of the boys have injuries or light injuries and would be categorised as yellow condition".
In the five-minute navy video, the boys are quiet as they sit on their haunches, legs bent in front of them.
At present, the only way out of their refuge is by diving through the flooded caves, but the route is extremely challenging and none of the boys can even swim, much less scuba dive. A fellow boy tells him they already said this, and then the rescuer assures them that "Navy SEALs will come tomorrow, with food and doctors and everything".
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He told Sky News: "That was the only basis we had".
One boy replies: "Oh. It was all speculation and pure luck that they were there".
"Monday. Monday. You have been here 10 days". "If the cave system (floods) it would make access impossible to the kids".
Pray that the rescue workers are wise as they piece together a rescue plan, and ask that God would strengthen these fearless boys as they battle fatigue and fear in the darkness of the cave. Waters in the cave must recede to safe levels before the boys can be safely extracted, experts say.
"Taking them in the water would be extremely unsafe for the kids and the coach - but also for the rescuers".
Rescue workers were scouring the hills above the cave network for other possible entry points or avenues to drill down to the trapped footballers, but the small size of the cave where they have found refuge could make that unsafe.
Thai navy SEAL divers and rescue workers from other countries made initial progress through a narrow passageway early Monday after passing through a key chamber Sunday whose high, murky waters had previously blocked their progress.
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In the dramatic video footage of the moment when the divers reach the group, nine days after they disappeared, a diver with a British accent is heard talking to the group.