In waters about 28 kilometers off the southeastern city of Ulsan, Jin was able to hold on to a buoy overnight before asking for help directly to a nearby fishing boat, which came to his rescue around 4:30 p.m. on Friday.

Jin's son, 10, who was on a motor boat waiting for him to come back, told his mother about Jin's disappearance by phone.

Jin's wife, who reported his disappearance to the rescue authorities, said her husband has 10 years of diving experience and was able to stay longer out at sea. "Luckily, he could save enough strength to ask for help by himself," she said.

His diving suit, coupled with higher water temperatures of 25-26 C, also helped him maintain his body temperature, rescuers said.

Jin showed symptoms of dehydration and low body temperature at the time of his rescue. But he was fit enough to be released from the hospital where he was taken.

The other scuba diver who joined the outing and went missing with Jin was rescued at 4:30 p.m. on Thursday. (Yonhap)