A powerful earthquake has paralysed Japan's northern island of Hokkaido, killing at least seven people, triggering landslides and knocking out power to its 5.3 million residents.
The death toll from the 6.7-magnitude, pre-dawn quake was likely to rise as rescuers searched houses buried by landslides.
About 33 people were missing and 300 were injured, public broadcaster NHK said. Four people were in cardio-pulmonary arrest, a term used before death is officially confirmed.
The quake was the latest in a string of natural disasters to batter Japan after typhoons, flooding and a record-breaking heat wave within the past two months.
Aerial footage showed dozens of landslides exposing barren hillsides near the town of Atsuma in southern Hokkaido, with mounds of red earth and toppled trees piled at the edge of green fields.
The collapsed remains of what appeared to be houses or barns were strewn about.
"It came in four big jerks - boom! boom! boom! boom!" one unidentified woman told NHK. "Before we knew it our house was bent and we couldn't open the door."
Prime Minister Shinzo Abe said 25,000 Self-Defence Force troops would be deployed for rescue operations.
The island lost its power when Hokkaido Electric Power Co shut down of all its fossil fuel-fired power plants after the quake as a precaution.
It was the first time since the utility was established in 1951 that had happened.
Almost 12 hours later, power was restored to parts of Sapporo, Hokkaido's capital, and Asahikawa, its second-biggest city.
The government said there was damage to Hokkaido Electric's Tomato-Atsuma plant, which supplies half the island's 2.95 million households. It could take a week to restore power fully to all residents, Industry Minister Hiroshige Seko said.
All trains across the island were halted.
The quake hit at 3.08am on Thursday at a depth of 40km, with its epicentre about 65km southeast of Sapporo, according to the Japan Meteorological Agency.
Hokkaido's main airport was closed, at least for the day.
The closure comes just days after Kansai Airport, another major regional hub, in western Japan, was shut by Typhoon Jebi, which killed 11 people and injured hundreds.
