An earthquake of magnitude 6.4 has toppled several buildings in the south Taiwan city of Tainan, killing at least three people.
Rescue teams were trying to reach people trapped in rubble after the high intensity quake struck early on Saturday as people were sleeping.
A baby and one other person died after a high-rise residential block collapsed. More than 220 people have been rescued.
President Ma Ying-jeou is on his way to Tainan, a city of two million people.
The quake was shallow, meaning its effects would have been amplified, the US Geological Survey (USGS) said.