Strong earthquakes strike China's Qinghai province and Japan's Kyushu region

CHINA/JAPAN - An earthquake with a preliminary magnitude of 7.1 struck Japan's southern Kumamoto prefecture on Tuesday, knocking out power to thousands of homes, stopping rail services and triggering warnings for tsunamis and aftershocks.

Companies including Sony 6758.T and TSMC 2330.TW, the world's largest contract chipmaker, have plants in the area of the quake.

A Sony spokesperson said the company was checking the situation. TSMC did not immediately respond to a request for comment.

The Japanese government issued emergency earthquake warnings for Kumamoto, Nagasaki, Kagoshima, Fukuoka, Saga, Oita, and Miyazaki prefectures, all on Japan's southern Kyushu island. A tsunami warning for a wave measuring 1 m (3.28 feet) was issued after the earthquake, the Japan Meteorological Agency said.

Japan is one of the world's most earthquake-prone countries, with a tremor occurring at least every five minutes. Located along the "Ring of Fire" of volcanoes and oceanic trenches partly encircling the Pacific Basin, Japan accounts for about 20% of the world's earthquakes of magnitude 6.0 or more.

A massive earthquake in Kumamoto 10 years ago killed 275 people and injured a further 2,739, according to an official count.

Kyushu Electric Power said about 40,000 homes had lost power as a result of the quake, while railway company JR Kyushu said that it had suspended services, including its high-speed bullet trains.

There were no irregularities reported at the nuclear power stations in the area, Japan's nuclear regulation authority said.

Meanwhile, in a separate report, Reuters said a magnitude 5.7 earthquake struck remote Xinghai county in the northwestern Chinese province of Qinghai on Tuesday at 11:16 a.m. (0316 GMT), with a second quake of magnitude 5.8 following 18 minutes later, the ⁠China Earthquake Networks Centre said.

Additional tremors, with one of magnitude 5.0, shook the region later in the afternoon, it said.

The quakes had a focal depth of 10 km (6.2 miles), with the epicentre located in a sparsely populated, high-altitude area about 244 km (152 miles) from Xining, the capital of Qinghai. Noticeable tremors were felt in Xining, state-run Xinhua news agency said.

Authorities have not yet received any reports of casualties, but some buildings and roads in at least seven nearby villages have been damaged to varying degrees, Xinhua said citing preliminary checks by local authorities.

Emergency response teams were already en route to the remote epicentre, and the tremors had also triggered limited landslides on nearby mountainsides, state media reported earlier.

(Reporting by Ethan Wang, Xiuhao Chen and Ryan Woo; Anton Bridge, Kantaro Komiya, Mariko Katsumura and Hina Suzuki; Writing by John Geddie; Editing by Chang-Ran Kim and Kate Mayberry)