TOKYO -- A strong earthquake jolted Kumamoto Prefecture in southwestern Japan on Jan. 3, the Japan Meteorological Agency said.
The tremor, which struck at 6:10 p.m., measured lower 6 on the 7-point Japanese seismic intensity scale in some areas of the prefecture. There was no threat of a tsunami, the agency said. There were no immediate reports of casualties or damage to properties.
The quake, which struck at a depth of 10 kilometers and had an estimated magnitude of 5.0, registered a lower-6 on the Japanese intensity scale in the Kumamoto Prefecture town of Nagomi, a lower-5 in some other areas of Kumamoto Prefecture, a 4 in the Chikugo district of Fukuoka Prefecture, and a 3 in parts of Saga, Nagasaki, Oita and Miyazaki prefectures as well as in other parts of Kumamoto Prefecture.
Two nuclear power plants -- Genkai Nuclear Power Station in Saga Prefecture and Sendai Nuclear Power Station -- are operating normally, their operator Kyushu Electric Power Co. said.
According to Kyushu Railway Co. (JR Kyushu), bullet train services between Hakata and Kumamoto on its Kyushu Shinkansen Line were suspended as of 7 p.m. for inspections on its tracks. Some trains on JR Kyushu local lines in Kumamoto Prefecture were delayed although no cancellations occurred.
Kumamoto Airport's runway was temporarily closed for safety inspections but was subsequently reopened.
The Kyushu Expressway was closed between Miyama-Yanagawa Interchange in Fukuoka Prefecture and Kumamoto Interchange.
Chief Cabinet Secretary Yoshihide Suga told a news conference that the government set up a task force on the earthquake at the prime minister's office and is doing its best to gather information on damage from the temblor.
Suga urged residents and those staying in quake-hit areas to pay close attention to information on the quake from TV, radio and other media and calmly take action.
Experts have warned that aftershocks registering up to a lower-6 could occur over the next week.