Japan mobilized 20,000 rescue workers on Hokkaido on Thursday after being wracked by a magnitude-6.7 earthquake just south of Sapporo, Hokkaido island's main city, and multiple aftershocks.

NHK broadcasting put the death toll at eight people, including six in the township of Atsuma, where landslides engulfed homes. A further 33 persons were missing. Around 130 people had sustained minor injuries, it said. A mudslide in Sapporo left several cars half buried.

"The shaking was really terrible," an unidentified survivor told NHK as rescuers used backhoe vehicles and shovels to sift through soil and rocks.

Read more: Japan's earthquake and volcano risks

Emergency shutdowns at fossil fuel-fired power plants cut electricity to the entire island — the size of Austria — leaving all trains, including high-speed services, halted, said Hokkaido Railway Co.

The outage also affected hospitals, subways, ATM money dispensers, and mobile phone networks.

Telephone provider NTT East made available public phones still linked by landlines.

A week to restore power

Industry Minister Hiroshige Seko said the Hokkaido Electric Power Co. might need a week to restore power fully to all 5.3 million residents.

Damage was reported at the island's key Tomato-Atsuma power plant.

Landslides engulfed homes near the township of Atsuma

Seko said mobile generators were being sent to hospitals. Additional power deliveries from Japan's mainland were planned. Even with stopgap measures, thousands would be without power for some time, he said.

Emergency power was cooling spent fuel at the Tomari Nuclear Power Station, which has been shut since Japan's 2011 Fukushima earthquake and tsunami.

Read more: Japan recognizes first Fukushima disaster radiation death

Main airport shut

Hokkaido's main aviation hub, New Chitose Airport, was reportedly shut for at least Thursday. Roof tiles and water lay on terminal floors. Three other outlying airports on Hokkaido were said to be operating.

At central Hokkaido's scenic town of Biei, residents lined up outside of supermarkets, clearing shelves of water, toilet paper and food, reported Associated Press.

The magnitude-6.7 earthquake struck southern Hokkaido at 3:08 a.m at a [shallow] depth of 40 kilometers (24 miles), Japan's Meteorological Agency said.

Japan still recovering from Typhoon Jebi

Hokkaido's earthquake comes just days after Typhoon Jebi devastated western Japan, including floodwaters that closed Osaka's Kansai Airport.

Domestic flights would resume Friday from Kansai, said Prime Minister Shinzo Abe.

Jebi was the worst typhoon to hit Japan in 25 years and claimed at least 11 lives.

Japan's hot northern hemisphere summer also brought deadly hot temperatures and devastating downpours from moisture-laden air masses over Hiroshima.

ipj/sms (AP, AFP, Reuters)