Update at 9pm:

At least four of the 12 boys have been rescued from the cave so far, a senior member of the rescue team revealed.

Update at 8.40pm:

A reporter identified the first two boys rescued as Prajak Sutham and Natthawut Hakumsai, both 14.

Lieutenant-General Kongcheep Tantrawanit told the Agence France Presse that four other boys have reached chamber three, where rescue workers had set up a base. They are expected to walk out of the cave shortly.

Update at 8.20pm:

The first two of the 12 boys have been rescued from the flooded Tham Luang cave, according to a local rescue official.

Although local officials had estimated the earliest time for the first boy to be rescued from the cave to be around 9pm local time, the local media reported that the first boy exited the cave at 5.37pm.

A second boy followed at 5.50pm.

Tossathep Boonthong, chief of Chiang Rai’s health department and part of the rescue team told Reuters:

“Two kids are out. They are currently at the field hospital near the cave.

“We are giving them a physical examination. They have not been moved to Chiang Rai hospital yet.”

Thai TV station Spring News earlier tweeted that three boys was rescued.

Once rescued from the cave, the boys and their coach will receive treatment at the Chiangrai Prachanukroh hospital for at least a day or more. Their family members will only be allowed to visit them once medical check-ups are completed in 48 hours.

Dr Thongchai Lertwilairattanapong, an inspector general of the Public Health Ministry in charge of Chiang Rai, said all the victims could be discharged from hospital within five days.

Update at 7.20pm:

Heavy showers in the afternoon promised to undo days of efforts by the team to drain floodwater from the cave.

Update at 4.30pm:

One of the operation leaders told reporters that the operation will span two to three days depending factors such as the weather.

Major General Chalongchai Chaiyakorn, an army commander, told reporters:

"The time duration is... about two to three days, which depends on other factors like the weather."

Original article:

An operation to rescue a group of boys and their soccer coach trapped in a cave at Khun Nam Nang Non Forest Park at the northern province of Chiang Rai, Thailand, has commenced, with 18 divers sent in. The divers, consisting 13 international and five Thai nationals, went into the cave at 10am local time, reports The Straits Times.

The boys who have been trapped since June 23 are estimated to emerge from the Tham Luang cave earliest at about 9pm local time (about 10pm in Singapore).

Mr Narongsak Osottanakorn, a former provincial governor who is leading the effort said at a press conference:

"Today is D-day. The boys are ready to face any challenges.

"Everything is ready. The boys are ready and willing to come out. The doctors and medics are ready. The parents are ready."

Mr Narongsak said that the divers are able to proceed on foot to the third chamber.

He added that Sunday is the best day for the rescue operation as most of the path is walkable.

Thai government releases graphic about #thamluangcaverescue . Full face masks; 2 divers accompanying 1 boy; guided by rope. When facing a very narrow path, they will release the tank from back and slowly roll tank & guide the boy through. They walk from Chamber 3 to mouth of cave pic.twitter.com/pLUKa8lHfd — Nick Beake (@Beaking_News) July 8, 2018

very dangerous Thai cave rescue begins, this is the narrowest part of the cave. pic.twitter.com/Bzwk1dzi6U — #Thinker (@areta) July 8, 2018

In an earlier tweet, Bangkok Post reporter, Wassana Nanuam, wrote that the operation would start by recovering four of the 12 boys first.

Tweeted the reporter:

“Sending support and prayers to the Seal unit and the first four kids to come out safe.”

Announcements of the rescue were made by the Thai authorities earlier on Sunday as the threat of a heavy rain loomed closer, with dark rainclouds observed over the skies at Thailand’s north. Stormy weather is also forecasted for the next two weeks.

Other reporters also tweeted on the announcements.

He won't say if the boys have to dive - just says today is best day because most of path is walkable #ThamLuangCave @MsKateLyons — michael safi (@safimichael) July 8, 2018

An area around the cave was evacuated to facilitate the operation.

The downpours could undermine efforts by rescuers to drain the Tam Luang cave complex in order to get the group out. Even worse, none of the boys can swim or have any experience diving.

Furthermore, the dark and narrow passageways into the cave make it tremendously difficult for the boys to get out. These passageways, which are sometimes no more than 0.6m wide, can pose challenges to even some of the world's leading cave divers.

The 12 boys, aged between 11 and 16, as well as their coach, 25, had gone missing while exploring the Tham Luang cave after a soccer practice session on June 23.

Officials have also ruled out the possibility of looking for shafts at the mountaintop for an alternative rescue route.

Mae Sai police commander Komsan Saardluan made the announcement:

“Assessing the situation now, it is necessary to evacuate the area for the rescue operation.

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

A photo released by the Royal Thai Navy shows Thai divers inside the cave, where a line has been established to pump fresh air in.

Nonessential personnel were also removed so as to preserve the oxygen level.

Meanwhile, free food is delivered and served to the personnel involved in the massive rescue operation which involves about 130 Thai and international divers.

Mr Gong Hui, a Chinese diver involved in the operation said sustained pumping had removed millions of litres of water from the cave, leading to receding water levels.

The operation thus far has been marred by difficulties.

On Thursday night, a former member of Thailand's elite Navy SEAL unit died after running out of oxygen during a dive. Several rescuers seeking alternative routes into the cave were also seriously injured after a vehicle skidded off a dirt track.

In light of the challenges, Tesla chief Elon Musk announced in a tweet that his team from SpaceX, his rocket company, is building a “kid-size submarine” so the boys could be transported out.

Got more great feedback from Thailand. Primary path is basically a tiny, kid-size submarine using the liquid oxygen transfer tube of Falcon rocket as hull. Light enough to be carried by 2 divers, small enough to get through narrow gaps. Extremely robust. — Elon Musk (@elonmusk) July 7, 2018

Read the tweet:

“Got more great feedback from Thailand. Primary path is basically a tiny, kid-size submarine... Light enough to be carried by 2 divers, small enough to get through narrow gaps. Extremely robust.”

He added that the submarine would take about eight hours to build and another 17 hours to move it to Thailand.

The Thai defence ministry earlier said that Mr Musk’s team of engineers, which specialises in drilling and exploration should reach the cave on Sunday. The team consists of engineers from Tesla, Mr Musk’s electric car company, Space X, his rocket company and Boring, a tunnelling and construction firm, added a spokesman from Boring.

The spokesman said that there were two or three engineers who have reached the site in Thailand already, with more help on the way.

He also said that the various company representatives were in discussion with the Thai government to see how they could help.

Not Space-X. But a Thai version of ⁦@elonmusk⁩ idea of an air-filled tube for trapped boys to get out, being tested near #Thamluangcave pic.twitter.com/udsKAdHLgY — Jonathan Head (@pakhead) July 8, 2018

In an earlier suggestion, Mr Musk also proposed using a nylon tube which would inflate to form an underwater air tunnel.