The strong quake was felt widely across Japan, including shaking of four on Japan's seven-point scale in the capital Tokyo.
"As far as damage, casualties and structural damage are being assessed", he said, adding that sections of the bullet train had been suspended due to power outages. Tokyo Electric Power Co. said that some 860,000 homes were without power as a result of the quake, according to government spokesperson Katsunobu Kato.
The Japan Meteorological Agency said the quake had a magnitude of 7.3, raising it from a preliminary magnitude of 7.1.
Aerial footage broadcast by NHK showed a hillside that collapsed onto a highway in Fukushima region, severing the road.
There were no immediate reports of injuries.
Police in Miyagi Prefecture say the quake has lifted up about 10 meters of another section of the expressway.
There were no immediate reports of significant damage, though local news broadcast images of a landslide on a highway.
The quake came almost 10 years since a more powerful quake caused a massive tsunami to hit Fukushima prefecture on March 11, 2011, killing 16,000 people and causing three nuclear reactors to meltdown at the Fukushima Daiichi nuclear plant.
While there was no tsunami warning generated by the quake, those near coastal areas were urged to move to higher ground as a precaution due to the likelihood of aftershocks.
Some people were taking shelter at evacuation centers, and were being warned to practice social distancing because of the coronavirus pandemic.