Four people are dead and 375 others injured after an estimated magnitude-6.1 earthquake struck a wide area of western Japan including Osaka, Kyoto, Hyogo and Shiga prefectures on June 18.

According to the Osaka Prefectural Government and prefectural police, Rina Miyake, a 9-year-old girl, was crushed under a falling wall outside Takatsuki Municipal Juei Elementary School. Minoru Yasui, 80, was also crushed under a collapsed wall in Osaka's Higashiyodogawa Ward. They were pronounced dead at hospital. Motochika Goto, 85, also died in the Osaka Prefecture city of Ibaraki. A woman in her 80s was also confirmed dead after she was crushed by a chest of drawers in Takatsuki, Osaka. At least 259 people were injured in Osaka, Kyoto, Hyogo, Shiga and Mie prefectures.

A glass window lies shattered at a store in Ibaraki, Osaka Prefecture, at 9:40 a.m. on June 18, 2018, after a powerful earthquake struck western Japan. (Mainichi)

Toshiyuki Matsumori, director of the Japan Meteorological Agency (JMA)'s Earthquake and Tsunami Observation Division, warned at a news conference on the morning of June 18 that up to lower 6 earthquakes could hit the area over the next week or so.

The temblor hit at around 7:58 a.m., measuring a lower 6 on Japan's 7-point seismic intensity scale in Osaka's Kita Ward and the Osaka Prefecture cities of Takatsuki, Hirakata, Ibaraki and Minoo, the JMA said. The quake caused major disruptions of train services across the Kansai region, affecting many commuters during rush hour.

A total of 20 fires broke out in the city of Osaka, the Osaka Prefecture cities of Takatsuki, Suita and Minoo, and the Hyogo Prefecture city of Amagasaki, the Fire and Disaster Management Agency said.

Smoke billows from a house in Takatsuki, Osaka Prefecture, on June 18, 2018. (Mainichi)

Tokaido Shinkansen bullet train services were suspended between JR Maibara and Shin-Osaka stations, and Sanyo Shinkansen Line services were stopped between Shin-Osaka and Okayama stations. Tokaido Shinkansen operations were resumed at 12:50 p.m., but trains are traveling at reduced speeds in the affected section. Services on the Sanyo Shinkansen Line were restarted by 2:58 p.m.

Many local train services in Osaka, Kyoto, Nara and Hyogo prefectures have been halted due to the quake.

Runways at Kansai International Airport were closed at 8 a.m. but were reopened after no problems were found. No serious damage to its terminal building has been confirmed. An air conditioner suspended from the ceiling on the second floor of Osaka International Airport's north terminal fell down after the quake, but nobody was injured.

Passengers get off a train near JR Osaka Station after it came to an emergency halt due to a powerful earthquake that struck western Japan, at 9:11 a.m. on June 18, 2018. (Mainichi)

Nuclear reactors in Oi, Mihama and Takahama in Fukui Prefecture are operating normally, according to their operators. According to Kansai Electric Power Co., a total of 170,000 households were without power at one point.

The earthquake, with a focus about 13 kilometers underground in northern Osaka Prefecture, registered a lower 6 on the Japanese intensity scale in northern Osaka Prefecture, the meteorological agency said. The areas that felt that intensity include Osaka's Kita Ward and the cities of Takatsuki, Hirakata, Ibaraki and Minoo, also in Osaka Prefecture, according to public broadcaster NHK.

Children are evacuated to the playground of a school in Toyonaka, Osaka Prefecture, after a powerful earthquake struck western Japan, at 8:30 a.m. on June 18, 2018. (Mainichi)

The JMA said that the earthquake's intensity in the southern area of Kyoto Prefecture hit an upper 5 on the same scale, while parts of Shiga, Hyogo and Nara prefectures experienced a lower 5.

The quake did not cause tsunami, the agency said.

(Mainichi)