The rescue of young footballers from a Thai cave complex continued for a second day on Monday with the mission chief promising more "good news" after four of the 13 were saved. A fifth boy was rescued on Monday afternoon, a Royal Thai Navy official said. No other details on him were immediately available. Seven more boys and the coach are still trapped. Sundays surprisingly quick extraction of the initial batch of four, who were guided out of a network of flooded tunnels by elite divers, fueled optimism that the others would also be quickly rescued. "All the equipment is ready. Oxygen bottles are ready," rescue operations chief Narongsak Osottanakorn told reporters on Monday afternoon after announcing the second phase of the rescue bid had begun. "In the next few hours we will have good news." Thais have been fixated on the crisis, hoping desperately for the safe return of the 12 boys and their 25-year-old football coach, after they ventured into the Tham Luang cave complex after practice and became trapped by rising waters on June 23. The saga has also dominated global headlines, with the team spending nine days unaccounted for inside the cave, before British divers found the emaciated and disheveled group huddling on a muddy bank above the flooding. Authorities then struggled to determine the best way to save the "Wild Boar" football team, with the group stuck on a shelf more than four kilometers (2.5 miles) inside the cave in pitch darkness. Among the ideas were drilling an escape route through the mountain, or leaving them for months until the monsoon season ended and the flooding subsided. But with oxygen levels inside dropping to dangerous lows and the prospect of heavy rains flooding the area completely, authorities decided they had to move quickly and take the group out through the water-filled tunnels. Dozens of foreign divers and other experts from around the world were brought to help the rescue effort, working alongside Thai Navy SEALs. None of the boys had scuba diving experience and that they could easily panic while swimming underwater in darkness. The death of a former Thai Navy SEAL diver who ran out of oxygen in the cave on Friday underscored the danger of the journey even for professionals. But after the first four emerged late on Sunday afternoon, hopes began to rise of a fairytale ending to the ordeal. The first four boys rescued from the cave were in good health and demanding fried rice in hospital on Monday, Narongsak said. They were flown by helicopter to the Chiang Rai Prachanukroh hospital, located at the heart of Chiang Rai province, about 70 km (40 miles) away from the cave. "The four children are fine. The children complained that they were hungry and wanted holy basil stir-fried rice," Narongsak told reporters on Monday, referring to a popular Thai dish. Officials have yet to confirm the identities of the four boys freed. Narongsak on Monday said their identities were being protected out of respect for the families of those still trapped inside the cave. Officials last week said they would bring the fittest people in the group out first, but Narongsak later said that whoever was ready first would be escorted out. A source involved in the rescue mission who saw two of the four boys walk out of the cave told Reuters that they looked tired but healthy, adding that one even looked "vivacious and fresh". He did not give further details. "Imagine marathon runners. Its like when they reach the finish line exhausted," said the source. At the hospital in Chiang Rai, green canvas sheets had been put up to block the entrance from view. Ambulances were on standby to receive the next batch of boys who are expected to be plucked from the cave. Medical staff involved in the rescue mission told Reuters their first assessments when the boys arrive at the hospital will focus on their breathing, signs of hypothermia and an airborne lung infection known as “cave disease” which is caused by bat and bird droppings and can be fatal if untreated and allowed to spread to other parts of the body.