Tens of thousands of Japanese households remain without power, after a powerful earthquake left at least four dead and more than 100 injured, and severed transport links to the country's northeast.
Companies including a giant chipmaker and Toyota Motor Corp raced to assess the impact of the magnitude 7.4 quake, which struck shortly before midnight on Wednesday.
Supply chain disruptions could put more pressure on already strained global output of smartphones, electronics and cars.
The tremor revived memories of the 11 March 2011 disaster in the same area, and left Shinkansen bullet train service indefinitely suspended, with at least one major highway to the region closed for safety checks.
Earthquake-affected residents shelter in a gymnasium in Soma, Fukushima Prefecture, on Thursday. Credit: CHARLY TRIBALLEAU/AFP via Getty Images
Areas of Tokyo lost power immediately after the quake, though most regained it within three hours.
But some 24,270 households serviced by Tohoku Electric Power Co in northeast Japan remained without electricity on Thursday, although the firm said it expected most will have supply restored later in the day.
Prime Minister Fumio Kishida said four people had died and that the government would be on high alert for the possibility of further strong tremors over the next two to three days.
At least 107 people were reported injured, several of them seriously, with 4300 households still without water by mid-morning.
Renesas Electronics Corp, the world's biggest maker of automotive microcontroller chips, said it was checking for quake damage at three plants in Japan.
Among them is its advanced Naka plant in Ibaraki prefecture, which closed for three months following the March 2011 quake and for a shorter time after a quake in 2021. It had to halt production last year because of a fire, exacerbating a global chip shortage that is forcing auto companies to curb output.
The quake, initially measured at magnitude 7.3 but later revised up to 7.4 by the Japan Meteorological Agency, hit at 11.36pm on Wednesday just off the coast of Fukushima prefecture at a depth of 60 kilometres.
The 2011 quake and tsunami off Fukushima — commemorated across the country less than a week ago — left about 18,000 dead.
A tsunami warning was issued but cancelled early on Thursday morning. Some areas reported a rise in the sea level but no serious damage was immediately reported.
The 2011 disaster also set off meltdowns at the Fukushima Daiichi nuclear power plant. No abnormalities were reported at any nuclear power plants, although authorities had earlier said a fire alarm had been triggered at a turbine building at the crippled plant.
Damaged pavement blocks on the ground in front of JR Fukushima Station, which seem to have been cracked due to the impact of the earthquake in Fukushima on Thursday. Source: AFP, Getty / STR/JIJI PRESS/AFP via Getty Images
Toyota said it had cancelled the day shift at two factories in northeast Japan after workers evacuated the plants during their evening shift on Wednesday. The automaker said it will decide on the evening shift later.
