A 7.2-magnitude earthquake shook Taiwan, the largest seismic event to strike the island in at least 25 years, killing four people, wounding others, and triggering a tsunami warning for southern Japan and the Philippines, which was subsequently removed.
Taiwan's authorities reported four deaths and more than 50 injuries in the hilly, thinly populated eastern county of Hualien, where the epicenter was located.
According to reports, at least 26 buildings have fallen, with more than half in Hualien, trapping about 20 people and requiring rescue efforts.
Taiwanese television stations broadcast video of buildings at dangerous angles in Hualien, where the quake occurred close offshore about 8 a.m. (GMT) as people were heading to work and school.
According to Taiwan's Central Weather Administration, the quake struck at a depth of 15.5 kilometers (9.6 miles).
Japan's meteorological office said that numerous minor tsunami waves hit sections of the southern prefecture of Okinawa before downgrading the earlier tsunami warning to an advisory. It estimated the earthquake's magnitude at 7.7.
The Philippines Seismology Agency also issued a warning to inhabitants in coastal regions of various provinces, asking them to evacuate to higher ground.
Taiwan also issued a tsunami warning but reported no harm, and the Pacific Tsunami Warning Center in Hawaii subsequently announced that the chance of devastating tsunami waves had gone.
Aftershocks were still felt in Taipei, according to a Reuters witness, with more than 25 recorded by Taiwan's central meteorological service.
According to Chinese official media, the quake was felt in Fujian province, and a Reuters witness reported feeling it in Shanghai as well.
The Taipei city administration stated there were no reports of severe damage, and the city's MRT was back up and running shortly after the tremor.
According to Taiwan's official national news agency, the quake was the most powerful to strike the island since 1999, when a 7.6-magnitude tremor killed over 2,400 people and destroyed or damaged 50,000 structures in one of Taiwan's worst-ever quakes.
According to Taiwan's Central Weather Administration, the earthquake had the second-highest strength of a "Upper 6" in Hualien County, on a scale of 1 to 7.
According to the Japan Meteorological Agency, in an Upper 6 earthquake, most unreinforced concrete-block walls collapse, and individuals are unable to stand or move without crawling.