TOKYO – A powerful earthquake struck Kumamoto Prefecture on Thursday night, killing at least nine people and injuring more than 780, the Kumamoto prefectural disaster response headquarters said Friday.

The headquarters confirmed that the magnitude-6.5 quake killed eight people in Mashiki, and one in Kumamoto in the prefecture. The quake registered a maximum 7 on the Japanese seismic intensity scale of 7.

As of 1 p.m. Friday, 784 people had been injured, including nine in Saga and two other neighboring prefectures, according to the Fire and Disaster Management Agency of the Internal Affairs and Communications Ministry. Fifty-three people were seriously injured.

In Kumamoto Prefecture, about 15,200 people had taken refuge at 399 emergency evacuation sites.

The Japan Meteorological Agency named the earthquake the 2016 Kumamoto Earthquake on Friday. Kumamoto Gov. Ikuo Kabashima asked Prime Minister Shinzo Abe to designate the quake as a devastating disaster.

Frequent aftershocks have occurred, significantly affecting electricity and gas, as well as the Kyushu Shinkansen line and other transportation systems.

According to the agency, there had been 129 aftershocks as of 1 p.m. Friday, with one measuring an upper 6 on the Japanese intensity scale of 7 and another measuring a lower 6. Two aftershocks were lower 5, and 16 measured 4 on the scale.

Compared to past quakes of similar size, the Kumamoto quake has had a significant number of aftershocks, the agency said. It dispatched a task force survey team to the quake-hit areas Friday morning.

“There is a high risk that furniture may fall down, and a landslide could occur in areas that experienced strong jolts,” Gen Aoki, chief of the agency’s earthquake and tsunami monitoring section, said during a press conference at 10:30 a.m.

“I want people to pay careful attention to future aftershocks and rainfall,” Aoki said. Rain is expected to fall Saturday night in Kumamoto Prefecture, he said.

The nine victims who died in the quake comprised four men and five women from 29 to 94 years old. Many of them died from suffocation or were crushed under collapsed houses, the prefectural disaster response headquarters said.

About 1,700 Self-Defense Forces personnel, about 1,920 police officers and about 2,937 firefighters from within and outside the prefecture were engaged in rescue operations. The police rescued about 60 people in disaster-hit areas, including Mashiki, where the quake measured 7 on the seismic intensity scale.

Kyushu Electric Power Co. said its Sendai nuclear power plant in Satsumasendai in Kagoshima Prefecture was operating normally. Kyushu Electric also confirmed that nothing unusual had occurred at its idled Genkai nuclear power plant in Genkai, Saga Prefecture.

As of 1 p.m. Friday, there were power outages at about 11,400 households in Kumamoto Prefecture. Saibugas Co. has suspended the gas supply to 1,123 households in Minami Ward, Kumamoto.

The water was shut off at about 25,000 households in the prefecture, the Health, Labor and Welfare Ministry said.

A total of 380 kindergartens, primary and middle schools in the prefecture were closed; their windows were broken and wall surfaces were damaged.

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