By Agencies

Boys and their coach who were saved from cave in northern Thailand lost 2kg on average, but are doing well.

The 12 boys and their coach who were saved from a cave in northern Thailand are doing well mentally and physically, a Thai health official has said, amid an outpouring of gratitude for those involved in their rescue.

Thongchai Lertwilairattanapong, an inspector for Thailand's health department, briefed reporters on the status of the Wild Boars football team on Wednesday. 

"From our assessment, they are in good condition and not stressed. The children were well taken care of in the cave. Most of the boys lost an average of 2kg," he said. 

Three in the group had minor lung infections, the senior health official added. 

The football team was rescued in batches over the course of Sunday, Monday and Tuesday in a high-risk operation. They will spend one week recovering in hospital after having been trapped inside the cave for more than two weeks. 

Congratulations and gratitude came in from across the world after it was reported that all 12 boys and their 25-year-old football coach were safe after being rescued from the Tham Luang cave complex, where they had gotten trapped inside on June 23. 

Thai Prime Minister Prayuth Chan-Ocha thanked people involved in the rescue in a televised address on Wednesday and said the mission had succeeded because of government efforts, the assistance of people within and outside Thailand and an outpouring of moral support. 

Acknowledging the 38-year-old former military diver who died while preparing the rescue, Prayuth said: "his honour, sacrifice and legacy will forever be in our hearts". 

The death of Saman Kunan, who passed out while placing oxygen canisters along the route divers had to take to get the children out, highlighted the danger involved in the three-day operation.

The multi-hour journey the team had to make towards the cave's mouth reportedly included navigating passageways as narrow as 40 centimetres while some of the boys did not know how to swim. 

US President Donald Trump and UK Prime Minister Theresa May were among those congratulating the team on their safe return on social media. 

"Delighted to see the successful rescue of those trapped in the caves in Thailand. The world was watching and will be saluting the bravery of all those involved," May tweeted.

Hooyah

The catchphrase "Hooyah" was trending on Twitter after Thai Navy SEALs used it repeatedly on their Facebook page as a rallying cry during the operation. 

Meanwhile, parents are anxiously waiting to be reunited with their children, something that might yet take some time due to doctors' fears over infections. 

The families of the four boys rescued on Sunday were allowed to visit them on Monday evening, but they were kept separated by a glass window. 

On Tuesday, the Thai prime minister said he wanted safety measures put in place at the cave site. 

"In future, we have to monitor the entrance and exit to the cave. This cave has become world famous … we have to install more lights inside the cave and put up signs," Prayuth told reporters in Bangkok.