At the site of the caves, volunteers assisting in the operation described the rescue attempt as a “now or never” scenario.
The boys and their coach are huddled together in a small chamber 4 kilometers (2.5 miles) inside the cave, surrounded by flood water and with a limited supply of oxygen.
To reach them, divers will need to successfully navigate a network of sprawling narrow tunnels, with officials close to the operation suggesting rescuers will use a “buddy” system, with each diver paired with a child. Extra oxygen tanks will also be positioned along the route.
Signs that a rescue operation was under way were evident in the hours leading up to the announcement as authorities installed a large green tarp around the cave entrance and removed media from outside of the camp to a separate location.
On the road leading to the tunnels, a near continuous convoy of trucks and military vehicles delivered troops and medical equipment equipment, including a large cache of oxygen tanks . On Saturday evening, numerous international military advisers could be seen entering the site, followed later by four monks in orange robes.
At the entrance to the site, a newly placed, thin white decorative flag fluttered in the wind, a Buddhist sign to indicate positive energy.