NEW potential rescue options have emerged as experts are racing to try and find a safe way to get 12 boys and their soccer coach out of a Thai cave before monsoonal rainfall arrives.

The Guardian reports that experts are looking into whether a tiny capsule could be sent down into the cave so that each boy can be placed into it and guided out of the Thai Tham Luang cave.

CNN reports that experts are looking at if there is a chimney or hole they could access instead of trying to get the boys out through the water.

It comes after Claus Rasmussen, who is part of the rescue team, said the boys had told divers they heard dogs barking, a rooster crowing and children playing while stuck deep inside the cave system.

But as the clouds draw in around the rescue site, experts are still training the boys in using scuba gear and swimming, so they can hopefully swim out of the cave one-by-one while accompanied with a diver.

The new suggestion of a capsule comes as Australia is sending more experts to help in the rescue.

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Thai boys and their soccer coach trapped in a flooded cave as a rescuer warns the next 24 hours will be critical to their survival.

“With the rescue effort at a critical stage, Australia is sending two more Australian Defence Force specialists with expertise in disaster recovery and planning,” Foreign Affairs Minister Julie Bishop said.

“An additional senior Australian Federal Police officer will also be deployed to support planning and coordination efforts.”

The experts will join six AFP diving experts that have been assisting the massive rescue operation since Saturday.

Ms Bishop’s update comes soon after a rescuer warned the boys will learn if they’ll survive in the next 24 hours.

The kids are reportedly being given a crash course in swimming and diving.

Aged between 11 and 16, the boys and their soccer coach, 26, have been inside the flooded Tham Luang network for 12 days after becoming stranded during a reported initiation ritual.

And on the eve of heavy monsoon rainfall, British cave explorer Vern Unsworth, who has been advising the rescue operation, believes that we will know whether the kids will survive in the next 24 hours.

“I think we’ll know in the next 24 hours … We’ll keep our fingers crossed — everybody needs to pray and hope for a good outcome,” Mr Unsworth told the BBC.

THE PLAN TO GET THEM OUT

The boys are being taught how to swim and scuba dive as they prepare to take on the “unbelievably dangerous” route of paddling two kilometres through the tunnel’s dark waters — a perilous journey which would take four hours.

Mr Unsworth, who is based in Chiang Ra, said that heavy rainfall has caused the water levels within the cave to rise further.

“The main thing is to try to get the children to safety. We have to keep hoping,” Mr Unsworth said.

Under this plan. the boys would be dressed in wetsuits, boots and helmets, and divers would use an 8mm static rope to guide them out.

They are likely to be provided with oxygen from a navy diver’s supply.

A number of “stage tanks” have been put 25 to 50 metres along the cave system, so the boys can get to oxygen if needed.

Divers working on the rescue have warned of the boys through the dark and dangerous waters still in the cave, especially since they are untrained.

“We are talking kilometers of transport under the water with zero visibility,” said Claus Rasmusen, a certified cave diving instructor based in Thailand who has been helping Thai SEAL team with logistics. “It’s difficult.”

This is the amount of rainfall predicted by the weekend, as experts race to find a way to get them out beforehand.

CHILEAN MINER’S ADVICE FOR BOYS

One of the Chilean miners who was trapped underground for 69 days in 2010 is raising funds to travel to Thailand and help the rescue effort.

“I’m going to see what’s possible,” Mario Sepulveda told AFP.

“I’m calling someone from the [Chilean] government to try to get some money together. I think it’s important as a country for us to be there, after what we miners went through.”

“I would love to go. I think it would be extremely important to support the families, give them a hug. Words of encouragement are important.”

Sepulveda sent a message, saying “hang in there”.

“What we need here is for the Thai government to put in a lot of money, and whoever else wants to donate, and get professional divers in there to get those boys out now,” he said.

“They need to teach them to dive as quickly as possible.”

BOYS MAY BE FREED ‘AT DIFFERENT TIMES’

The Thai official overseeing the rescue operation said the boys and their coach may not all be extracted at the same time depending on their health.

Chiang Rai provincial Governor Narongsak Osatanakorn said on Wednesday that “all 13 may not come out at the same time. If the condition is right and if that person is ready 100 per cent, he can come out.”

Authorities insist they won’t begin the rescue mission that has gripped the whole world until it was safe to do so.

“We have to be 100 per cent confident that there is no risk to the boys before we evacuate,” Narongsak Osottanakorn, Chiang Rai provincial governor, told reporters.

“We will take care of them like they are our own children,” he said.

The group are being taught how to use diving masks and breathing apparatus, he added, but from the safety of the muddy bank which for now remains their sanctuary.

He said authorities will evaluate their readiness each day and if there is any risk will not proceed.

He said the team is currently recuperating.

A video released by Thai Navy SEALS showed them in good spirits.

Authorities are still determining the best way to get the team out of the cave, options that include diving.

Authorities are also pumping out water around-the-clock aware of the bad weather forecast in the days ahead, removing around one centimetre each hour in a massive draining operation.

“We want to evacuate all 13 people as soon as possible but I don’t want to specify day and date,” Thailand’s junta leader Prayut Chan-O-Cha said later.

FAMILIES CLING ONTO HOPE

In a heartening message to families waiting in outside the cave, footage was released by the Thai Navy SEAL featuring 11 of the 12-strong team.

Each made a traditional Thai greeting gesture to the camera before introducing themselves by their nickname and saying “I’m in good health”.

Several of the boys in the frame are wearing protective foil blankets and are accompanied by a smiling diver in a wetsuit.

Also seen is the 25-year-old coach, who went with the boys down the cave after football training on June 23.

A one-minute video clip ends on a jovial note, with one of the 12 young footballers saying he was forgotten in the round of introductions, sparking laughter.

The images have delighted a Thai nation that has held its breath for a successful outcome to a challenging rescue kilometres inside one of the country’s longest caves.

‘HE IS THINNER’

In the video the boys, who have spent 11 nights underground, appear relaxed and much more alert than when they were when British divers found them late on Monday huddling on a muddy ledge above surging underground waters.

Outside the cave the mother of one of the boys teared-up as she watched the clip on a television screen, saying she was “glad” for a glimpse of her son.

“He is thinner” she said as she ran her finger over his image — a sign of the heartache the saga has brought to relatives of the trapped 13.

Several Navy SEAL divers have deployed along with medics vowing to stay with the group while the challenging process of evacuating the “Wild Boar” team begins.

Thai authorities say the focus is now building up the boys’ physical and mental strength after an ordeal that has left them emaciated.