A 6.1-magnitude earthquake jolted Taiwan on Thursday, the US Geological Survey said, disrupting traffic and injuring 17 people.
In the capital Taipei, highrises swayed while some panicked schoolchildren fled their classrooms in eastern Yilan county, according to reports.
The quake was felt across the island and a highway connecting Yilan and Hualien was shut down, authorities said.
An official at the Hualien county fire department told AFP that two people were injured by falling rocks. The National Fire Agency said one, a Malaysian male tourist, had been rushed to hospital in a critical condition after suffering a cardiac arrest, a leg fracture and head injuries.
The agency added that there were also 15 injuries reported around Taipei and that two buildings in the city were temporarily evacuated due to structural damages after the tremor.
Taipei's metro system was closed for over an hour for safety checks following the quake, while the Taiwan Railway Administration also suspended some of some of its services in the east coast for several hours, officials said.
The quake struck at 1:01 pm (0501 GMT) at a depth of 19 kilometres (11.8 miles) in eastern Hualien county.
The central weather bureau also put its magnitude at 6.1. The USGS had earlier measured it as a 6.0 quake, but later revised it to 6.1.
"The tremor could be felt for 33 seconds, which is considered quite long ... It could be felt all over Taiwan and it's the first quake above 6.0 magnitude this year," said Chen Kuo-chang, director of the bureau's seismological centre.
Social media users posted photos of the glasses at a restaurant being shattered by the quake, and of the exterior tiles of a department store building falling.
"I live on the 21st floor, the building swayed so much that I was almost scared to death," one user posted.
The Japan Meteorological Agency warned that people living near the coast could notice some effects on sea levels, but said there would be no tsunami, and "there is no concern about damage".
Hualien, a scenic tourist hotspot, was struck by a 6.4-magnitude earthquake last year that killed 17 people and injured nearly 300 people.
Taiwan lies near the junction of two tectonic plates and is regularly hit by quakes.
The island's worst tremor in recent decades was a 7.6-magnitude quake in September 1999 that killed around 2,400 people.