STORY: More than 200 aftershocks have shaken Hualien - the eastern part of Taiwan that was hit hard by the island's big quake on April 3.
The new shaking started Monday and ran through the night, causing previously damaged buildings to tilt further.
Several were left leaning badly, but there were no reports of casualties.
The affected buildings have been left empty since the 7.2 magnitude earthquake hit the largely rural and sparsely populated area earlier this month, killing at least 17 people.
Elsewhere on the island, including in the capital, Taipei, buildings swayed throughout the night, with the largest of the many quakes registering a 6.3 magnitude.
The world's largest contract chipmaker, TSMC, meanwhile evacuated some staff from factories on the island's west coast.
It said in a statement that it does not expect any impact on operations.
Taiwan President Tsai Ing-wen, on her Facebook page, called on people to stay alert and not to panic in the event of more earthquakes.
