A powerful quake struck southern Taiwan before dawn on Saturday near the city of Tainan, toppling a 17-story apartment building where more than 100 people are feared trapped.
A baby girl and a 40-year-old man have been confirmed dead, according to a government official. Media reported a third death.
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Taiwan struck by powerful quake
A magnitude 6.4 earthquake topples a 17-storey apartment building in the southern Taiwanese city of Tainan.
Rescuers mounted hydraulic ladders and a crane to scour the wreckage and pluck more than 120 survivors to safety, with at least 26 taken to hospital, a fire brigade official said.
"I was watching TV and after a sudden burst of shaking, I heard a boom. I opened my metal door and saw the building opposite fall down," said a 71-year-old neighbour who gave his name as Chang.
A plumber, he said he fetched some tools and a ladder and prised some window bars open to rescue a woman crying for help.
"She asked me to go back and rescue her husband, child, but I was afraid of a gas explosion so I didn't go in. At the time there were more people calling for help, but my ladder wasn't long enough so there was no way to save them."
The magnitude 6.4 quake was centred 43 kilometres southeast of Tainan, at a depth of 23 kilometres, the U.S. Geological Survey said. It struck just before 4 a.m.
Several aftershocks shook Tainan afterwards, Taiwan's Central Weather Bureau said.
One elderly woman, wrapped in blankets, was strapped to a board and slowly slid down a ramp to the ground as the cries of those still trapped rang out. Rescuers used dogs and acoustic equipment to pick up signs of life in the rubble.
"There are 60 households in that building," said Tainan fire department information officer Lee Po Min, estimating that there might be about 240 people living there.
One city hospital said 58 people had been brought in, most of them with light injuries.
Taiwan President Ma Ying-jeou, speaking to reporters in the capital before leaving for the disaster scene, said authorities were not clear on the extent of the disaster.
"The disaster situation is not very clear yet. We will do our utmost to rescue and secure (survivors)," Ma said.
Several other buildings had also been damaged, including one that was pictured leaning at an alarming angle over a street in Tainan, a city of 2 million people, many of whom lived through a massive 1999 tremor that killed about 2,400 people.
Taiwan lies in the seismically active "Pacific Ring of Fire". Television quoted Tainan residents as saying the quake felt worse than the 1999 tremor, centred in central Taiwan.
Taiwan's Formosa TV said its reporters could hear the cries of people trapped inside the collapsed apartment tower as firefighters, police and troops swarmed the area.
Firefighters hosed down part of the building to prevent a fire while others used ladders and a crane to enter upper floors. The building appeared to have collapsed onto the first story where a child's clothes fluttered on a laundry line.
Some bullet train services were suspended to the south of Taiwan as inspections were carried out on the tracks for damage, Taiwan High Speed Rail Corp said in a statement.
"Collapsed buildings reported in Tainan, with rescue workers arriving on scene. The city government there has set up a level one emergency response centre. Onlookers are urged not to block access to emergency crews moving into the area," Taiwan's China Post newspaper said on its Web site.
Liu Shih-chung, an official with the Tainan city government, said the city had set up an emergency response centre.
According to the USGS, the last time Taiwan was struck by a quake of the same magnitude as Saturday's was in April 2015, but that one was deeper.