Three ambulances have been seen leaving the site of the Thai cave rescues amid speculation that all 12 boys and their coach have been rescued.

But in news that the world was waiting for, Royal Thai Navy SEALs confirmed on Facebook at 9.51pm AEST that the remarkable rescue operation for the Wild Boar football players had been completed after spending 17 days trapped in the flooded caves.

“Hooyah! 12 wild pigs and coaches out of the cave. Safe everyone. This time, waiting to pick up 4 Frogs,” the jubilant post said.

The final boy and coach were expected to be accompanied by a doctor and three Royal Thai Navy SEALs, all of whom have been in the cave with the group since day 1.

The speculation intensified as the three boys were transported to hospital.

The ninth Wild Boar was successfully transported by ambulance to hospital, while the 10th boy is being conveyed for further treatment in a helicopter.

#ThamLuangRescue: 2nd helicopter has taken off from heliport near cave complex and is now flying towards Chiang Rai Prachanukroh Hospital https://t.co/h5GsGrk9rE pic.twitter.com/pqp0v8zJ9U

— Pichayada P. (@PichayadaCNA) July 10, 2018

Earlier on what is the third day of the extraordinary rescue mission, Thai Prime Minister Prayut Chan-o-cha told reporters the rescued boys had been given anti-anxiety medication – the same he uses to help him relax when shooting – for the journey out of the cave.

Thai TV reported that the 11th child rescued is the smallest. He is believed to be 11-year-old Chanin Wiboonrungrueng and is reported to be in good health.

Earlier on Tuesday, a ninth boy and a 10th boy were rescued as hopes rose that the remaining four boys and their coach will finally see daylight after more than a fortnight underground.

UPDATE at 6:07pm: Helicopter has taken off carrying the 9th boy and is heading to Chiang Rai.

RT @TNAMCOT: ฮ.ยกตัวขึ้นจากลานจันกะผัก คาดนำหมูป่าคนที่ 9 ส่งโรงพยาบาล #ThamLuang #พาทีมหมูป่ากลับบ้าน #ถ้ำหลวง #Thailand #ThaiCaveRescue pic.twitter.com/xNBUly4IGk

— Richard Barrow (@RichardBarrow) July 10, 2018

Nineteen divers began the final rescue operation just after 1pm (AEST), with plans to get the whole group out by late on Tuesday.

The mission commander expects all five could be out in coming hours.

“We expect that everybody will be out today, the children and coach and everybody will be out today,” Chiang Rai acting governor Narongsak Osatanakornas said, according to reporters at the scene.

Four more boys were successfully rescued on the second day of an audacious and risky operation.

An ambulance leaves the site of the rescue efforts. Photo: Getty

The four are “safe and conscious” in hospital after being brought out of the Tham Luang Nang Non caves in Chiang Rai late on Monday night.

In total, nine of the 12 young footballers are now safe and being cared for after four were removed on Sunday, the first day of the operation.

The operation to remove the boys and their coach is expected to take longer than the earlier extractions because rescue workers who have been supporting the operation will also need to follow them out.

Today’s final rescue mission to extract the last four Thai boys and their football coach from #ThamLuangcave will take longer than previous nights because, in addition, 3 Thai NavySEALS and a Thai army medic who have stayed with the boys since they were found will also come out.

— amanda hodge (@hodgeamanda) July 10, 2018

So far, the dive teams have stuck to their plan of guiding no more than four boys at a time, and Mr Narongsak had earlier not ruled out the possibility of leaving one survivor on his own for an extra day, saying “the best number is four”.

The group have been trapped for more than two weeks after heavy rains flooded the sprawling cave network, comprising caverns connected by tight passages.

Elite Australian divers have been assisting in the painstaking rescue operation.

Among them is Adelaide anaesthetist and cave diver Dr Richard Harris, 53, who has been praised for his contribution so far.

The extensive pumping system used to drain water from the cave system. Photo: Royal Thai Navy Facebook

Mr Narongsak said Monday’s rescue operation, involving 18 divers and a support team of 100, had taken nine hours, two hours less than the rescues on Sunday.

“We have more expertise than yesterday,” he said.

Workers have been toiling around the clock to pump water out of the cave as they battle against time to avoid further expected heavy rains.

Oxygen levels in the chamber where the boys sought refuge have been falling since the operation began, adding further pressure to finish the rescue.

Mr Narongsak said Thailand’s Prime Minister, Prayuth Chan-ocha, who travelled to the cave site on Monday, visited the eight rescued boys in hospital.

The boys and their coach went exploring in the massive Tham Luang Nang Non cave on June 23 after football practice, and were cut off when a rainstorm flooded the cave.

A massive international search operation was launched and it took 10 days to locate the boys, who had taken shelter on a dry slope deep in the complex.

The death on Friday of a former Thai navy Seal underlined the risks.

The diver, the first fatality of the rescue effort, was working in a volunteer capacity and died on a mission to place air canisters along the passage to where the boys are, necessary for divers to safely travel the five- to six-hour route.

-with agencies