A 6.8 magnitude earthquake hit the sparsely populated southeastern part of Taiwan on Sunday, the island's weather bureau said, derailing train carriages and causing a convenience store to collapse.
The weather bureau said the epicentre was in Taitung county, and followed a 6.4 magnitude temblor on Saturday evening in the same area, which caused no casualties.
The U.S. Geological Survey measured the quake at a magnitude 7.2 and at a depth of 10 km (six miles).
Taiwan's fire department said two people were trapped in a building housing a convenience store that collapsed in Yuli and two people had been rescued, while three people whose vehicle fell off a damaged bridge were rescued and taken to hospital.
The Taiwan Railways Administration said three carriages came off the rails at Dongli station in eastern Taiwan after part of the platform canopy collapsed. The fire department said one person was injured.
The U.S. Pacific Tsunami Warning Center issued a warning for Taiwan after the tremor but later lifted the alert. Japan's weather agency also lifted an earlier tsunami warning for part of Okinawa prefecture.
The quake could be felt across Taiwan, the weather bureau said. Buildings shook briefly in the capital Taipei.
Science parks in the southern cities of Tainan and Kaohsiung, home to major semiconductor factories, said there was no impact on operations.
Taiwan Semiconductor Manufacturing Co (TSMC), the world's largest contract chipmaker, said there was "no known significant impact for now".
Taiwan lies near the junction of two tectonic plates and is prone to earthquakes.
More than 100 people were killed in a quake in southern Taiwan in 2016, while a 7.3 magnitude quake killed more than 2,000 people in 1999.