Rescuers were frantically searching on Wednesday for survivors of a 7.1-magnitude earthquake that shook southern Japan, killing at least 13 people, knocking out power to thousands of homes and rupturing roads across the region. Eight people were pulled from the rubble of a partially collapsed shopping mall near the city of Kumamoto that was torn apart by an apparent explosion about an hour after Tuesday’s earthquake. Of them, three have died. Mall operator Aeon said four workers at the Kumamo...