Regardless, it was the largest earthquake to hit Taiwan in 25 years, and was felt in parts of Japan and China too.

Officials in Hualien county said that work and school were suspended following the earthquake. On social media, users posted images of tilted and half-collapsed buildings and landslides in the area. Authorities sent an alert to residents that they should seek cover nearby, crouch down and “stay calm.”

As far away as Taipei and New Taipei City, the quake left commuters stranded in train cars as the high speed rail and metro system were paused.

Taiwan is a key manufacturing hub for many of the world’s advanced computer chips. A spokesperson for Taiwan Semiconductor Manufacturing, or TSMC, said that some operations had been suspended.

Taiwanese officials issued a tsunami warning for the coastal regions of the island, and Japanese officials warned residents in the southwestern Okinawa island chain to evacuate to higher ground.

On Yonaguni, one of the Okinawa islands, an 11-inch tall tsunami hit 20 minutes after the initial quake, and officials expect more tsunamis to continue and become more intense.

The initial tsunamis from a major Japanese earthquake in March 2011 similarly began at a few dozen inches and grew to over 30 feet, leading to a nuclear meltdown and triggered one of the biggest nuclear disasters in history.

A tsunami as high as 10 feet may hit the main Okinawa island, local officials warned.

Inuma reported from Tokyo. Vic Chiang and Pei Lin Wu in Taipei contributed to this report.