Taiwan's strongest earthquake in a quarter century rocked the island during the morning rush hour Wednesday, damaging buildings and highways and causing the deaths of four people.

Taiwan's national fire agency said four people died in Hualien County and at least 57 were injured in the quake that struck just before 8 am. The local United Daily News reported three hikers died in rockslides in Taroko National Park near the offshore epicentre.

A five-storey building in Hualien appeared heavily damaged, collapsing its first floor and leaving the rest leaning at a 45-degree angle. In the capital Taipei, tiles fell from older buildings and in some newer office complexes, while debris fell from some building sites. Schools evacuated their students to sports fields, equipping them with yellow safety helmets. Some also covered themselves with textbooks to guard against falling objects as aftershocks continued.

Train service was suspended across the island of 23 million people, as was subway service in Taipei, where a newly constructed above-ground line partially separated. The national legislature, a converted school built before World War II, also had damage to walls and ceilings.

Traffic along the east coast was at a virtual standstill, with landslides and falling debris hitting tunnels and highways in the mountainous region. Those caused damage to vehicles, though it wasn't clear if anyone was hurt.

Despite the quake striking at the height of the morning rush hour just before 8 am, the initial panic faded quickly on the island, which is regularly rocked by temblors and prepares for them with drills at schools and notices issued via public media and mobile phone.

Authorities said they had only expected a relatively mild quake of magnitude 4 and accordingly did not send out alerts.

Still, the earthquake was strong enough to scare people who are used to such shaking.

“Earthquakes are a common occurrence, and I've grown accustomed to them. But today was the first time I was scared to tears by an earthquake,” Taipei resident Hsien-hsuen Keng said. ”I was awakened by the earthquake. I had never felt such intense shaking before.”

She said her fifth-floor apartment shook so hard that “apart from earthquake drills in elementary school, this was the first time I had experienced such a situation.”

Hualien was last struck by a deadly quake in 2018, which collapsed a historic hotel and other buildings. Taiwan's worst quake in recent years struck on September 21, 1999, with a magnitude of 7.7, causing 2,400 deaths, injuring around 100,000 and destroying thousands of buildings.

The Japan Meteorological Agency said a tsunami wave of 30 centimetres (about 1 foot) was detected on the coast of Yonaguni island about 15 minutes after the quake struck. Smaller waves were measured in Ishigaki and Miyako islands. Japan sent military aircraft to gather information about the impact around the Okinawa region.

Taiwan's earthquake monitoring agency gave the magnitude as 7.2 while the US Geological Survey put it at 7.4. It struck about 18 kilometres (11.1 miles) south-southwest of Hualien and was about 35 kilometres (21 miles) deep. Multiple aftershocks followed, and the USGS said one of the subsequent quakes was 6.5 magnitude and 11.8 kilometres (7 miles) deep. Shallower quakes tend to cause more surface damage.

The earthquake was felt in Shanghai and several provinces along China's southeastern coast, according to Chinese media. China and Taiwan are about 160 kilometres (100 miles) apart. China issued no tsunami warnings for the Chinese mainland.

Residents of China's Fujian province reported violent shaking, according to Jimu News, an online outlet. One man told Jimu that the shaking awakened him and lasted about a minute.

In the Philippines, residents along the northern coast were told to evacuate to higher ground, but no major tsunami was reported about three hours after the quake.

Villagers in the provinces of Batanes, Cagayan, Ilocos Norte and Isabela were asked not to return to their homes until the tsunami alert was lifted, Philippine Institute of Volcanology and Seismology Teresito Bacolcol said.

Japan's Chief Cabinet Secretary Yoshimasa Hayashi said there has been no report of injury or damage in Japan. He urged the residents in the Okinawa region to stay on high ground until all tsunami advisories are lifted. He cautioned people against disinformation and urged them to stay calm and assist others.

The Pacific Tsunami Warning Center said there was no tsunami threat to Hawaii or the U.S. Pacific territory of Guam. About three hours after the earthquake, it said the threat had largely passed for all areas with waves being reported only in Taiwan and southern Japan.

Taiwan lies along the Pacific “Ring of Fire," the line of seismic faults encircling the Pacific Ocean where most of the world's earthquakes occur.