A strong earthquake with a magnitude of 5.5 jolted the Tokai region early Tuesday, injuring seven people in Mie, Aichi, Gifu and Nara prefectures.
Prefectural officials said four people suffered minor injuries in Mie, one in Aichi, one in Nara and another in Gifu.
The temblor, which struck at around 1:43 a.m., registered a lower 5 on the Japanese intensity scale to 7 -- strong enough to crack concrete walls -- in central Aichi, the Meteorological Agency said.