The bravest boys in the world... but when will their rescue take place?
Thai cave conditions improve as officials plan extraction attempt to rescue the trapped schoolboys, writes Patpicha Tanakasempipat
The Thai governor in charge of rescuing 12 boys and their football coach from a cave says the co-operating weather and falling water levels over the last few days have created conditions for an attempted extraction of the group.
Narongsak Osatanakorn said authorities are waiting for two big groups of volunteer divers to arrive later today, after which they will be ready to begin the operation of bringing the group out.
He said: "The plan that I've held on to from the beginning is that we have to bring the kids out and the determining factor of this plan is to have as little water as possible."
But he said while floodwaters have drained as much as possible, "if it rains and adds to it again, we don't know what other risk factors we will have to face". He also warned about higher carbon dioxide levels in the cave.
The warning came a day after a Thai diver died during part of the rescue operation - marking a deadly turn in what started out as a celebration of one of the boys' birthdays at the Tham Luang cave complex in northern Chiang Rai province.
A team of Thai Navy Seals, soldiers, police and volunteers have been working around the clock to try and drain the cave. The boys, aged between 11 and 16, who are not all capable swimmers, are being taught to take on a treacherous dive through narrow, muddy, submerged passageways.
Alternative rescue methods include stocking the cave with supplies and an oxygen line to keep the boys alive for months until Thailand's monsoon season ends, or drilling a shaft down into the cave from the forest above.
Narongsak said they would have to drill through 600m of fragile limestone rock to reach the boys and were discussing drilling angles.
Videos of the boys after their discovery on Monday showed them looking frail, thin and exhausted. But they appear to have remained in good spirits, and Narongsak Osottanakorn said yesterday that the boys' health was the "best yet" - as were the conditions to spring them to safety.
Heartfelt letters delivered by divers from the boys to their family waiting outside the cave spoke of them feeling healthy and strong and wanting to go home. They said they did not want their parents to worry - and that they would like some fried chicken when they get home.
One, identified as Tun, wrote: "Mom and Dad, please don't worry, I am fine. I've told Yod to get ready to take me out for fried chicken. With love."
Another, called Mick, wrote: "Don't be worried, I miss everyone. Grandpa, Uncle, Mom, Dad and siblings, I love you all. I'm happy being here inside, the Navy Seals have taken good care. Love you all".
"Night loves Dad and Mom and brother, don't worry about me. Night loves you all," wrote Night, using the Thai letter-writing style of referring to himself in the third person.
One touching note came from one whose name was not clear: "I'm doing fine, but the air is a little cold, but don't worry. Although, don't forget to set up my birthday party."
Another asked their teacher not to give them a lot of homework.
In a letter of his own, the coach, Ekapol Chanthawong, apologised to the boys' parents. "To the parents of all the kids, right now the kids are all fine, the crew are taking good care. I promise I will care for the kids as best as possible. I want to say thanks for all the support and I want to apologise to the parents," he wrote.
Thirteen medical teams are ready round the clock outside the cave - each with its own helicopter and ambulance - one for each of the 12 boys and their coach trapped inside.
Each boy will have a devoted medical unit consisting of at least one doctor, two nurses, a paramedic and an ambulance, sources said.
Medical staff involved in the mission said their first assessments will focus on the boys' breathing, signs of hypothermia and an airborne lung infection known as ''cave disease'' which is caused by bat and bird droppings and can be fatal if it is untreated and spreads to other parts of the body.
After the initial assessment, the group would be driven by ambulances to makeshift helipads and airlifted to the Chang Rai hospital some 70km away.
Medical staff have been conducting regular drills at the camp, practising ferrying patients in stretchers hundreds of metres through thick mud from the cave's entrance to the road where the ambulances - assembled from across the country - wait.
Getting to the muddy bank where the boys sought refuge takes a nearly 11-hour round trip through 4km of winding submerged pathways and fast-flowing freezing water.
The death in the cave of the former Thai Navy Seal underscores the challenge that awaits the boys.
"Hypothermia is the scariest condition. The body temperature drops as the water is very cold," said a rescuer, adding that a whole section of the hospital had been set aside for the boys' treatment.
"But what we're most concerned with is infections. There are all kinds of diseases in the cave, from bats, from dirty water. Everything in there is very dirty."
Histoplasmosis, also known as "cave disease", is a concern, as is leptospirosis, an infection caused by bacteria which can lead to severe bleeding from the lungs or even meningitis.
When Chilean miners were rescued after more than two months trapped underground in 2010, some were suffering from pneumonia from inhaling dust, others with dental and eye problems.
Apart from the physical illness, there is also the psychological strain of living in the dark hundreds of metres underground. Insomnia, depression and post-traumatic stress will all have to be monitored.
© Associated Press