At least nine people have died after a second earthquake hit Japan's southern island of Kyushu. Authorities report more than 800 injured - at least 53 seriously - and tens of thousands displaced on the island.
The 6.4-magnitude earthquake, thought to be one of the aftershocks of the earlier quake, struck at 0:03 a.m. local time on Friday (15:03 UTC).
Japanese broadcaster NHK reported that around 860 people were injured during the tremors, while tens of thousands of people were evacuated.
"As far as we can tell from infrared images from a police helicopter, there appears to be a significant number of houses destroyed or half-collapsed," Japanese Disaster Minister Taro Kono told the AFP news agency. "There are fears the number of injured could rise."
The quake reportedly brought down walls and a number of houses in the town of Mashiki, located some 900 kilometers (560 miles) southwest of Tokyo. An unknown number of people were trapped in the buildings and one of them was unconscious, according to NHK. Kyushu Electric Power said more than 16,000 households in and around Mashiki were without electricity.
Local media showed firefighters tackling a blaze and watermelons falling from shelves at a supermarket in Kumamoto, located around 1,900 kilometers west of Tokyo. High-speed train services were also suspended as a precaution.
Government seismologist Gen Aoki urged residents to be on guard for more aftershocks and warned wet weather in coming days could make the recovery effort difficult.
"Please do not go near damaged houses and structures that are about to collapse," Aoki said at a Friday morning briefing.
Japan's military has dispatched aircraft and helicopters to the region to assess the damage, said Defense Minister Gen Nakatani.
Suga said no abnormalities had been reported at the Genkai Nuclear Power Plant in Saga prefecture or the Sendai Nuclear Power Station in Kagoshima prefecture.
The Sendai plant is 130 kilometers south of Kumamoto. The operator restarted two nuclear reactors last year, the first of two units running under updated regulations.
The first quake
Several buildings collapsed in an earlier quake that struck at 9:26 p.m. at a depth of 10 kilometers, with its epicenter in the Kumamoto region, according to the Japan Meteorological Agency.
More than 10 aftershocks were reported in the two hours after the quake. The first quake had a preliminary magnitude of 6.0 and was 23 kilometers deep. It was then followed 30 minutes later by another one with a 5.7 magnitude. No tsunami warning has been issued.
Japan is located at the junction of four tectonic plates and receives around 20 percent of the world's most powerful earthquakes. But strict building codes mean that even very powerful tremors do not usually cause widespread damage.
On March 11, 2011, a massive 9.0-magnitude earthquake sent a tsunami barreling into Japan's northern coast, killing nearly 20,000 people and triggering a meltdown at the Fukushima nuclear plant.
rs, jbh/kms (dpa, AFP, Reuters)