A delicate and extremely dangerous operation to rescue 12 Thai schoolboys and their football coach is hoped to deliver a dream result within the next few hours.

Authorities overseeing the rescue in Chiang Rai province in northern Thailand said the “first batch” of boys could be out around 9pm local time (12am AEST).

But while there were hopes the Wild Boars football team and their coach could all be out over a few hours, authorities say it may take several days.

From Thai officials on the ground RE first rescue inside Tham Luang cave: “Based on the complexity and difficulty of the cave environment it is unknown how long it might take and how many children would exit the cave (in first batch).” @SBSNews — Omar Dabbagh (@Omar_Dabbagh) July 8, 2018

"Because of the complexity of the cave and difficulty of the operation. it is unknown how long it will take before the team can bring out the first batch of boys,” the rescue’s Joint Command Centre said in a statement.



“The divers will work with medics in the cave to assess the boys’ health before determining who will come out first.”

In preparation police and security personnel blocked off roads leading to the hospital on Sunday (July 8).

AAP

This complex and extremely fraught extraction has rescuers taking as much time as possible to complete the delicate mission ahead.

"They cannot decide how many of them will be able to come out for the first operation,” authorities said.



“Based on the complexity and difficulty of the cave environment it is unknown how long it might take and how many children would exit the cave.”



Authorities have confirmed Australian AFP divers are involved in the mission.

'Boys to be split into four groups'

Earlier the Bangkok Post was reporting that the 12 boys would be divided into four groups, according to a source.

It said the first group will have four people, with the second, third and fourth containing three people.

The coach will be in the final group.

Coach Ekkapol Chantawong (left) is among the last 3 including 2 boys to be escorted by divers out of flooded #ThamLuang cave: Rescue authorities. #D-Day



File photo @ThaiSEAL FB page pic.twitter.com/xhG3V48Hhg — Bangkok Post (@BangkokPostNews) July 8, 2018

Eight Aussie divers in operation

Twitter @JulieBishopMP

Eight Australian divers are involved in the hazardous attempt to rescue a group of boys trapped in a Thailand cave for two weeks.

The divers entered the Chiang Rai cave on an 11-hour round trip to rescue the 12 boys and their soccer coach at 10am on Sunday (1300 AEST).

An Australian doctor went all the way through to the cave yesterday to give the boys a medical tick of approval, and cleared them for rescue today before coming out. AFP says he is currently a part of the rescue. @SBSNews — Omar Dabbagh (@Omar_Dabbagh) July 8, 2018

They are planning for two divers to accompany each boy back to the surface through the four kilometres of tight, muddy, water-filled passageways, some of which are less than a metre in diametre.

What we know:



✅ They are using full face masks

✅ There are two divers per boy

✅ They have to dive to the 3rd chamber

✅ They will then walk out to the entrance



Credit FB "พล.อ.ประยุทธ์" #ThamLuang #พาทีมหมูป่ากลับบ้าน #ถ้ำหลวง #Thailand #ThaiCaveRescue pic.twitter.com/y2SiL2fx5o — Richard Barrow in Thailand (@RichardBarrow) July 8, 2018

Six of the divers are with the Australian Federal Police, while another is an anaesthetist from Adelaide along with his diving partner.

A spokesperson for Foreign Minister Julie Bishop said the anaesthetist entered the cave on Saturday to check the boys' health and has been working closely with on-site doctors.

Australian media at the scene said the anaesthetist was called in at the request of British divers on the scene who were familiar with his expertise.

He has extensive cave-diving experience and it's understood he's acting as a private citizen.

The Australian divers, in support of the Royal Thai navy, have been deployed under the Australian Medical Assistance Teams humanitarian program.

This takes the total number of Australians from DFAT, Defence and AFP involved in the rescue operation to 19.

Australia is sending a medical specialist with cave-diving expertise to join the Aussie team of 17 from @AusFedPolice @DeptDefence @dfat helping Thai Government rescue 12 boys and soccer coach

🇦🇺🇹🇭 @NatTraumaCentre #AUSMAT #ThamLuangCave pic.twitter.com/Fk0zjsPmcN — Julie Bishop (@JulieBishopMP) July 7, 2018

'Today is the D-day'

A rescue operation began Sunday to extract 12 boys and their football coach who have been trapped for more than two weeks in a cave in northern Thailand, the head of the mission said.

"Today is the D-day. The boys are ready to face any challenges," rescue chief Narongsak Osottanakorn told reporters near the cave site.

18 divers have been sent inside the cave and the 13 waiting to be rescued have been informed. It's being reported that the earliest the boys will come out is 9pm tonight local time.

READ MORE Letters of hope and love from boys trapped in Thai cave

The rescue began 10am local time, shortly after officials cleared the area surrounding the cave in readiness for the rescue operation.

Osottanakorn confirmed all 13 inside the cave are "really healthy". He said the families of those inside accept the rescue plans.

Authorities made the call to proceed with the rescue as dark monsoon rain clouds loomed over the mountainous north of the country early on Sunday, potentially heightening risks at the cave where rescuers were still waging a "war with water and time" to save the boys.

"Assessing the situation now, it is necessary to evacuate the area for the rescue operation," said Mae Sai police commander Komsan Sa-ardluan over a loudspeaker earlier today.

AAP

"Those unrelated to the rescue operation, please evacuate the area immediately."

Media have been cleared from the staging area around the cave complex.

How the rescue is unfolding

Expert divers could spend days trying to rescue 12 schoolboys and their soccer coach, who are trapped inside a cave in northern Thailand.

How the Thai cave boys' rescue operation will play out.

The divers

At 10am on Sunday (1300 AEST) 18 divers entered the cave in Thailand's northern province of Chiang Rai, where 12 schoolboys and their soccer coach have been trapped for two weeks.

Thirteen of the divers are foreign, including eight Australians.

Some of the cave's passages are so slim, rescuers must remove their oxygen tanks in order to squeeze through.

SBS News

The retrieval

Retrieving the boys from the muddy bank on which they took refuge requires a nearly 11-hour round trip through 4 km of winding, submerged pathways, tunnels and fast-flowing, freezing water. Some of the submerged tunnels are less than a metre high.

Two divers will gradually escort each boy out, one at a time. The earliest divers will emerge is 9pm on Sunday (midnight AEST), but a Thai official says the rescue of all the boys could take up to four days.

Aftermath

Thirteen medical teams stand ready outside the cave, each with its own helicopter and ambulance, to assist each boy and their coach.

Medical staff have told Reuters their first assessments will focus on the boys' breathing, signs of hypothermia and an airborne lung infection known as 'cave disease'.

If efforts over the next few days fail, authorities have not ruled out laying an oxygen line and leaving the boys inside the cave for months until monsoon rains clear.

- with AAP, AFP, Reuters