A former Thai navy SEAL taking part in efforts to rescue 12 boys and their soccer coach trapped inside a flooded cave has reportedly died after running out of oxygen during a return dive. SEAL commander Arpakorn Yookongkaew announced at a news conference Friday that the rescuer, identified by The Guardian as Samarn Kunan, died during a mission to place oxygen canisters inside the cave where the boys have been trapped since June 23. Thai authorities have been examining several options to evacuate the boys from the cave before monsoon rains hit this weekend, including by training them to dive out with the help of oxygen masks. Experts had warned that such a move would be risky, as the boys are inexperienced divers. Two of the boys and their coach have also reportedly been diagnosed with malnutrition and exhaustion, a factor that may hinder the five-hour dive to escape.