The quake's epicentre was around 15 kilometres north of the port city of Hualien at a depth of around 8 kilometres, the USGS added.
There were no immediate reports of any destruction caused by the tremors. The USGS said there is "low likelihood of casualties and damage".
"Overall, the population in this region resides in structures that are resistant to earthquake shaking, though vulnerable structures exist," the organisation said.
It cautioned, however, that earthquakes in the past have triggered landslides.
Have felt three earthquakes here in #Taipei, #Taiwan in the last hour. And the second #earthquake lasted quite a while... pic.twitter.com/W6zgKYiM0v
— Evan Tzeng (@EvanTzeng) February 4, 2018
The 6.1-magnitude earthquake was one of five that struck at a shallow depth in the same area off Taiwan's eastern coast within two hours of each other on Sunday.
The other four were between 5.2 and 5.5 magnitude, according to the USGS.
Source: AFP
