 Engineers desperately tried to pump water out of the cave, but struggled, at least at first. At the start, no one really had any idea what to do, one volunteer said. Officials brought in whatever equipment they could think of, small water pumps, long pipes, knives, and shovels, but most of it was apparently unsuitable. They tried drilling into the mountainside, desperate to find cracks into the cave system they could squeeze into, and used drones with thermal sensors to try to locate the boys.