By Nectar Gan, Wayne Chang, Jerome Taylor, Antoinette Radford, Deva Lee and Maureen Chowdhury, CNN
From CNN's Wayne Chang
One person has been killed in Taiwan after a 7.4 magnitude earthquake hit the island, based on preliminary data from Taiwan's National Fire Agency (NFA).
The person was hiking in Hualien County, NFA said.
Officials are still gathering more information about casualties, according to NFA.
From CNN's Nectar Gan
Videos posted by Taiwan residents on social media and geolocated by CNN show some of the damage from a 7.4 magnitude earthquake that rocked the island early on Wednesday.
In the eastern county of Hualien, near the epicenter of the quake, social media footage showed several collapsed buildings and residents helping trapped people escape through the window of a damaged apartment complex.
At a road intersection, a crowd of morning commuters on scooters and motorbikes watched as a multi-storey red building tilted sideways, a separate video showed.
Another video from Hualien captured a massive landslide coming down the mountain, with clouds of brown dust swallowing a section of the road and buildings nearby.
In the capital Taipei, in the north of the island, a video showed a subway car shaking violently, with passengers holding onto the handles tightly.
From CNN's Wayne Chang
Taiwan is expected to be hit by aftershocks over the next three to four days following a 7.4 magnitude earthquake on Wednesday morning, according to the island's Central Weather Administration.
The aftershocks could be as strong as a magnitude 6.5 to 7.0, a spokesperson for the administration said at a news conference.
From CNN’s Wayne Chang and Manveena Suri
Beijing has offered relief assistance after a 7.4 magnitude earthquake hit Taiwan on Wednesday morning, according to China’s Taiwan Affairs Office spokesperson Zhu Fenglian.
“Relevant parties in the mainland were highly concerned and express their sincere condolences to the Taiwan compatriots affected by the disaster,” Zhu said.
She added they would “pay close attention to the disaster situation and aftermaths, and are willing to provide disaster relief assistance.”
Some background: China's ruling Communist Party claims Taiwan as its own territory, but it has never controlled the self-ruling democratic island.
From CNN's Wayne Change
Taiwanese President Tsai Ing-wen said she has "immediately instructed the administration to get on top of the situation and understand local impacts as soon as possible," following an earthquake that struck the island early on Wednesday.
Tsai has also instructed the administration to "provide necessary assistance, and work together with local governments to minimize the impact of the disaster," according to a post on her Facebook page.
From CNN's Wayne Change
People are trapped in Taiwan after a powerful earthquake that hit the island on Wednesday morning caused the collapse of at least 26 buildings, according to Taiwan's Central Emergency Command Center (CEOC).
There are reports of people trapped in seven of the buildings, CEOC added.
The collapsed buildings include 15 in Hualien County near the epicenter, CEOC said.
The quake has also affected power supplies, with more than 91,000 households without electricity, CEOC said, adding that the island's state-operated Taipower Company is currently working to fix the issue.
CEOC also noted that some train services in eastern Taiwan have been suspended, but it's estimated that they'll be operational again by the end of the day.
From CNN's Jerome Taylor
Taiwan’s east coast is breathtakingly rugged and a major tourist draw, its geography a testament to the powerful tectonic forces that lie underneath.
The island is located where the Philippines Sea Plate meets the vast Eurasian Plate. The result is a tear-drop-shaped island that boasts a towering spine of mountains running down its middle and an eastern coast that often experiences tremors.
Taiwan’s western side is where the majority of the population live, home to the largest cities, an extensive high-speed train network and much of the industrial heartland.
In contrast, the east coast is much less populated and rural. Winding roads and a much slower train line cling to steep cliffs and have to go through dozens of tunnels.
The city of Hualien itself is the gateway to many popular tourist sights including the famous Taroko Gorge and the dramatic Qingshui Cliffs, a 21-kilometer stretch of sheer cliffs that average more than 800m high.
To the south of Hualien lies many coastal spots that are particularly popular with surfers and cyclists as well as the Huadong Valley, also known as the East Rift Valley, which boasts many beautiful rural villages.
From CNN’s Himari Semans and Manveena Suri
All flights to and from Japan’s Naha Airport on Okinawa island have resumed after a tsunami warning issued for the area was downgraded, the airport's spokesperson Hideaki Tsurudo told CNN on Wednesday.
Okinawa was impacted by small tsunami waves under 30 centimeters (11 inches) following the earthquake in Taiwan, resulting in flights to be suspended. But no waves reached the airport and it was thereby reopened, according to Tsurudo.
From CNN’s Himari Semans and Manveena Suri
No casualties or damage have been reported in Japan following the 7.4 magnitude earthquake in Taiwan, according to Japanese Chief Cabinet Secretary Yoshimasa Hayashi.
The quake triggered tsunami warnings in Japan, but early reports show the first tsunami waves to be small, under 30 centimeters (11 inches), on the southern Japanese island of Okinawa.
But Hayashi, speaking at a press conference, said the second and third waves generated by the quake are expected to be bigger.
The tsunami warnings for Japan have been downgraded to an advisory, he said.
Still, Hayashi advised people in affected areas to remain on higher ground.
