A 6.3 magnitude earthquake struck just 34 km off the eastern city of Hualien in Taiwan on Friday, according to the island’s weather administration. This powerful tremor, which was the second strong quake in less than a day, shook buildings in the capital, Taipei, causing subway services to operate at lower speeds, Reuters reported.

The quake, with a depth of 9.7 km, follows a 5.7 magnitude tremor that hit off Taiwan’s northeastern shore late Thursday. “It was close,” said singer Hsieh Yu Wei, who pulled over on a Hualien coastal highway after receiving a government-issued quake warning.

Although there have been no immediate reports of damage, weather officials have warned of aftershocks that could reach a magnitude of 5.5 in the coming days, Reuters said. Approximately a dozen smaller quakes have already been recorded near Hualien since the major tremor on Friday morning.

Authorities have also issued warnings for potential landslides in mountainous areas, where heavy rains have already saturated the ground.

Taiwan, located near the junction of two tectonic plates, is highly susceptible to earthquakes. Earlier in April, Hualien experienced the island’s most severe earthquake in 25 years, resulting in nine fatalities and over 900 injuries.