The Meteorological Agency issued a false alarm shortly before 5 p.m. Thursday, warning that a strong earthquake was about to hit Nara and Osaka prefectures. It turned out to be a mild tremor.
The agency said the false alarm was triggered by some noise trouble that occurred in an underwater earthquake scale off Mie Prefecture.
"We apologize for causing problems to so many people," said Toshihiko Hashida of the agency during a press conference.