world. i'm joe johns in for fredricka whitfield. rescue teams have evacuated four of the boys. the rest of the team spending another night right now in the depths of that dark cave where they've been trapped for more than two weeks. rescue crews are plotting their next move as oxygen levels drop, monsoon rains move in threatening to seal off the cave. cnn has reporters on the scene. jonathan miller near the cave entrance and cnn's matt rivers outside the hospital where the four boys are now being treated. let's go first to jonathan miller. this was just an extraordinary rescue. eight boys and their coach still until the cave. what are we waiting for next rescue? do we have to wait another 15 hours or so?