A former Thai navy diver has died while taking part in efforts to rescue 12 boys and their football coach trapped in a flooded cave in Thailand, the BBC reports.
Petty Officer Saman Gunan lost consciousness on his way out of the Tham Luang cave complex, where he had been delivering air tanks.
The boys have been trapped for nearly two weeks in a chamber in the cave.
They ventured in while the cave was dry but were caught out by a sudden deluge of rain, which flooded the system.
The group was found by British rescue divers after 10 days in the cave, perched on a rock shelf in a small chamber about 4km (2.5 miles) from the cave mouth.
Teams of Thai and international divers have since supplied them with food, oxygen and medical attention, but there are mounting concerns about the oxygen level in the chamber, which officials said had fallen to 15%. The usual level is 21%.