Powerful earthquakes struck Japan, Mexico and China within hours of one another on Tuesday, prompting a tsunami warning in southern Japan and emergency responses in parts of Asia.

The strongest of the earthquakes, with a preliminary magnitude of 7.1, struck Japan’s Kumamoto prefecture, according to the Japan Meteorological Agency (JMA).

Speaking to reporters at her office in Tokyo, Japanese Prime Minister Sanae Takaichi said the extent of casualties and property damage was being assessed.

“We have already been informed that people have been injured,” Takaichi said.

“Power outages and fires have occurred in some areas, and there has also been damage to roads and bridges and the collapse of buildings. Above all, I ask everyone to take action to protect themselves, including evacuating to a safe location.”

Public broadcaster NHK showed several buildings on fire or collapsed, large cracks along roads, including an elevated highway, and a derailed goods train. More than 150,000 people were instructed to go to evacuation centres, the disaster management agency said.

TSMC 2330.TW, the world’s largest contract chipmaker, evacuated workers from its plant in the area as a precaution, a spokesperson for the firm said.

A spokesperson for electronics firm Sony 6758.T, which also has a plant there, said it was checking the situation.

Residents in the areas that felt the biggest tremors must beware of further strong quakes for about a week as well as the risk of landslides, an official for the Japan Meteorological Agency (JMA) said.

TRAINS HALTED, AIRPORT CLOSED

The Japanese government issued emergency earthquake warnings for Kumamoto, Nagasaki, Kagoshima, Fukuoka, Saga, Oita, and Miyazaki prefectures, all on Japan’s southern Kyushu island. The JMA also initially issued a tsunami warning for a wave measuring 1 m (3.28 feet) but later lifted it.

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.

Kyushu Electric Power said about 40,000 homes had lost power as a result of the latest quake, while railway company JR Kyushu said that it had suspended services, including its high-speed bullet trains. Kumamoto airport also shut its runway, as airlines diverted and cancelled flights.

Telecoms operators KDDI and Docomo said there was disruption to their mobile phone services due to power shortages and transmission-line failures.

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

In Mexico, a magnitude 5.8 earthquake struck near the coast of Puerto Madero early on Tuesday, according to the United States Geological Survey.

The earthquake occurred at a depth of 35km (21.7 miles). No immediate reports of casualties or damage were available.

Meanwhile, two earthquakes struck the remote county of Xinghai in China’s northwestern Qinghai province within 18 minutes of each other.

The first, measuring magnitude 5.7, struck at 11.16am local time (0316 GMT), according to the China Earthquake Networks Centre. A second earthquake of magnitude 5.8 followed at 11.34am.

Both earthquakes occurred at a depth of 10km (6.2 miles). Their epicentres were located in a sparsely populated, high-altitude area approximately 244km (152 miles) from Xining, the provincial capital.

Tremors were felt in Xining, China’s state-run Xinhua news agency reported.

Authorities had received no reports of casualties or collapsed buildings, while public order remained stable, Xinhua said. Emergency response teams were travelling to the epicentral area to assess conditions.

There was no immediate indication that the earthquakes in Japan, Mexico and China were connected. Earthquakes occurring in different parts of the world within a relatively short period do not necessarily share a geological cause.