Security personnel guard the entrance of a road leading to a trail on Mount Ontake in Nagano prefecture Tuesday, three days after the volcano erupted in central Japan. Jiji Press/AFP/Getty Images hide caption

itoggle caption Jiji Press/AFP/Getty Images

A photo taken from a Kyodo News helicopter shows Japan's Self-Defense Forces personnel rescuing climbers who were in critical condition near the top of Mt. Ontake Monday, before rescue operations were suspended. Kyodo /Landov hide caption

itoggle caption Kyodo /Landov

Shinichi Kuramoto of the Center for Deep Earth Exploration in Japan displays a replica of earthquake fault rock. TOSHIFUMI KITAMURA/AFP/Getty Images hide caption

itoggle caption TOSHIFUMI KITAMURA/AFP/Getty Images