Laos cave rescuers investigating ‘knocking response’ as focus shifts to newly discovered cave shaft

By Angie Puranasamriddhi and June Jeong, CNN Vientiane, Laos (CNN) — Rescuers in Laos say they are investigating a possible “knocking response” deep inside a flooded cave network where two men are believed to remain trapped. The development could indicate possible signs of life but rescuers stress they need to investigate further before saying for