An earthquake has toppled buildings in the south Taiwanese city of Tainan, killing at least 11 people.
The magnitude 6.4 quake struck just before 04:00 (20:00 GMT Friday) when most people were at home asleep.
A baby was among at least four people killed when a high-rise building, containing 100 homes, collapsed.
At least 30 people remain missing. Tainan's mayor said people were alive but trapped under the rubble and all means would be used to rescue them.
President Ma Ying-jeou, who toured the city of two million, said shelters would be set up for those who had lost their homes.
Television pictures showed rescue workers frantically trying to reach people trapped in collapsed buildings, using ladders to climb over piles of rubble.
One of the worst affected was the 17-storey Wei Kuan apartment complex, home to at least 256 people.
More than 200 people were rescued, but a baby, young girl and two adult men did not survive, officials said. At least 70 people were taken to hospital.
Interior Minister Chen Wei-jen said he feared more people may have been in the fallen apartment block than usual as families gathered to celebrate Chinese New Year.
He said investigators would examine whether the building's construction met requirements.
Residents told how they were able to escape from their homes in the block, using their own tools and ladders.
"I used a hammer to break the door of my home which was twisted and locked, and managed to climb out," one woman told local TV.
Another man tied clothes together to make a rope and lowered himself from the ninth floor to the sixth floor below, Apple Daily reports.
One Tainan resident said his bed turned over as the wall collapsed. "My home completely turned into debris. I didn't know what was happening. I was really frightened as I have never seen such an earthquake," he said.
A 35-year-old woman described how she and her two children were pulled from the rubble.
"Rescue workers broke through (the building) layer by layer. And they asked us to climb out but I said my children are too small to climb. So they dug a bigger hole. Then one rescue worker tried his best to climb in and take the children out. Then I slowly climbed out myself," she said.
The quake was shallow, meaning its effects would have been amplified, the US Geological Survey (USGS) said.
There have also been at least five aftershocks. The quake was felt in the capital Taipei, 300 km away.
Although the damage does not appear to be widespread, a number of tall buildings have been left leaning precariously.
There are also reports of power outages, and transport links have been disrupted on what is one of the busiest travelling days of the year ahead of the Chinese New Year holiday.
Taiwan lies near the junction of two tectonic plates and often sees tremors.
Beijing has offered assistance although at the moment at least, given the relatively limited scale of the disaster, it does not look as if much outside help is needed, the BBC's John Sudworth reports from the Chinese capital.
Back in 1999, when a 7.6 magnitude quake killed more than 2,300 people in central Taiwan, a similar offer of help from the mainland became embroiled in political wrangling, with Taiwan accusing China of exploiting the situation for its own political ends, our correspondent adds.