Residents of earthquake-prone Izu Peninsula in Shizuoka Prefecture are having an anxious day after being hit by a 5.3-magnitude quake Friday morning, following a similarly strong temblor that occurred late last night. Friday's quake injured at least seven people. A series of earthquakes that started Thursday have damaged about 20 houses and cut off tap water in certain areas in Izu, the Shizuoka Prefectural Government said.