There were no immediate reports of damage or injuries.
Both earthquakes struck on the coast of Hualien. The first one was centered about 19.2 kilometers southwest of Hualien County Hall and struck at a depth of 10.5 km, the bureau's Seismology Center said.
The earthquake's intensity, which gauges the actual effect of a quake, was highest in the northern half of Hualien County, measuring 4 on Taiwan's 10 level intensity scale, the CWB said.
The quake also reached an intensity of 3 in Taichung and Taoyuan cities and Nantou, Yilan, Changhua, Yunlin and Miaoli counties, and an intensity of 2 in Taipei, New Taipei, Tainan, Chiayi and Hsinchu cities and Hsinchu, Chiayi and Taitung counties, the bureau said.
The second quake's epicenter was nearly identical to that of the earlier one, located about 18.1 kilometers southwest of the Hualien County Hall, at a depth of 8.4 km, the CWB said.
The quake's intensity was also highest in Hualien County, where it measured 4, while Yilan County registered an intensity of 3, the bureau said.
The quake was also felt in New Taipei, Taichung, Taoyuan and Chiayi cities and Nantou, Yunlin, Changhua, Miaoli and Hsinchu counties at an intensity of 2, according to the bureau.
Source: Focus Taiwan News Channel