The 12 boys and soccer coach found in a partially flooded cave in northern Thailand after 10 days are mostly in stable medical condition and have received high-protein liquid food, officials said Tuesday local time, though it is still uncertain when or how they will be able get home.

The boys were found late Monday night during a desperate search that drew international help and captivated the nation. Video released early Tuesday by the Thai navy showed the boys in their soccer uniforms sitting on a dry area inside the cave above the water as a spotlight, apparently from a rescuer, illuminated their faces.

Chiang Rai provincial Gov. Narongsak Osatanakorn said the health of the boys and coach were checked using a field assessment in which red is critical condition, yellow is serious and green is stable.

"We found that most of the boys are in green condition," he said. "Maybe some of the boys have injuries or light injuries and would be categorized as yellow condition. But no one is in red condition."

When the group will be able to leave the cave isn't known. Flooding and other factors that could make their extraction dangerous. Experts have said it could be safer to simply supply them where they are for now. Thailand's rainy season typically lasts through October.

​

In the five-minute navy video, the boys are quiet as they sit on their haunches, legs bent in front of them.

"How many of you are there — 13? Brilliant," a member of the multinational rescue team, speaking in English, tells the boys. "You are very strong."

"Thank you so much," one of the boys says.

One boy, noticing the camera and hearing unfamiliar words, says in Thai, "Oh, they want to take a picture. Tell him we're hungry. I haven't had anything to eat."

Then the boy breaks into simple English, saying, "Eat, eat, eat," to which another voice responds in Thai that he already told that to the rescuer.

Boys receive liquid food, medicine

Narongsak said Tuesday that the missing were given high-protein liquid food, painkillers and antibiotics. He said doctors had advised giving the medicine as a preventative measure.

The boys, between ages 11 and 16, went missing with the 25-year-old after soccer practice on June 23 after they set out to explore the Tham Luang cave complex in a forest park near by the border with Myanmar.

A massive international rescue effort has been underway since, with rescue teams battling through thick mud and high water to try to reach the group in the cave network that stretches 10 kilometres into a mountain.

A military officer stands as he blocks the entrance of the Tham Luang cave complex. (Soe Zeya Tun/Reuters)

"Thai Navy seals have found all 13 with signs of life," Narongsak told reporters who have been following the increasingly desperate search that has gripped the country.

Relatives of the boys, who have been at a shelter near the cave hoping for a breakthrough, were seen cheering, smiling and receiving calls after getting the news. Rescuers shook hands and congratulated each other as occasional cheers broke out.

Difficult passageway

As the days wore on with the group missing, distraught family members had placed fruit, desserts, sugary drinks and sweets on mats near the cave as an offering to the spirits, which some people believe protect the cave and the forest.

Rescuers had been working on Monday to clear a constricted passageway for divers deep inside the flooded complex in a search operation that has been hampered by heavy rain.

Family members react after hearing the news that the missing players and coach have been found. (Sakchai Lalit/Associated Press)

Divers from Thailand's elite navy SEAL unit had been focusing on an elevated mound inside the cave that cavers have named Pattaya Beach, which could have provided the boys with a refuge when rains flooded the cave.

"The SEALs reported that ... they reached Pattaya Beach which was flooded. So they went 400 metres further where we found the 13 ... who were safe," Narongsak told the cheering group of reporters.

Members of a Thai rescue team can be seen on Monday, walking inside the cave complex where 12 boys and their coach went missing. (Tham Luang Rescue Operation Center via AP)

Capt. Jessica Tait from the U.S. Air Force's rescue support team said there were "lots of challenges" throughout the search, but that the effort had brought the country together.

"When you consider it there were lots of challenges when it comes to the elements ... when it comes to different courses of actions," Tait told reporters.

"But you know what I saw, I saw Thailand coming together."

What happens next

The next challenge will be getting the group out of the cave, which some have dubbed a "labyrinth."

Anmar Mirza, a leading American cave rescue expert, said many challenges remain for the rescuers. He said the primary decision is whether to try to evacuate the boys and their coach or to supply them in place.

"Supplying them on site may face challenges depending on how difficult the dives are," Mirza, co-ordinator of the U.S. National Cave Rescue Commission, said in an email. "Trying to take non-divers through a cave is one of the most dangerous situations possible, even if the dives are relatively easy. That also begets the question: If the dives are difficult then supply will be difficult, but the risk of trying to dive them out is also exponentially greater."

A military transport helicopter carries a drill machine to be used for the rescue. (Sakchai Lalit/Associated Press)

Narongsak said officials had met and agreed on the need to "ensure 100 per cent safety for the boys when we bring them out."

"We worked so hard to find them and we will not lose them," he said.

Prime Minister Prayuth Chan-ocha thanked the international experts and rescuers who helped locate the missing for their "tremendous efforts."

"The Royal Thai Government and the Thai people are grateful for this support and co-operation, and we all wish the team a safe and speedy recovery," Prayuth's office said in a statement.