More than 1,000 seismic events had been recorded as of Thursday in Kumamoto and Oita prefectures in the two weeks since a magnitude-6.5 earthquake struck central Kyushu, according to the Meteorological Agency.

The frequency, ranging from minor jolts to the magnitude-7.3 temblor that occurred two days after the initial April 14 quake, is unusually high, the agency said, noting the nation's total last year was 1,842. It warned people should stay alert for more earthquakes.

Major transportation lines have rapidly recovered in the region, with bullet train services on the Kyushu Shinkansen Line resuming on all tracks as of Wednesday. The Kyushu Expressway is expected to fully reopen on Friday.