The quake, which shook at a depth of 15.2 miles (24.4 km), had an epicenter 80 miles east of Sendai, Honshu, the U.S. Geological Survey (USGS) reported.
The quake triggered a 13-foot tsunami that swept cars, boats, debris, and buildings miles inland. Fires prompted by the quake burned up and down the coast, including setting aflame an oil refinery, according to The Associated Press.
The main quake and the waves of massive aftershocks shook buildings violently even in Tokyo, which is 231 miles southwest of the epicenter. At least 19 people have died, and injuries are being reported in the wider Tokyo area.
"The train network in the metropolitan area has been stopped!" Tokyo resident Tsuyoshishiga tweeted in Japanese an hour after the quake.
Three hours after the quake, 244 people have reported to the USGS that they have felt the shake. The farthest response was from Taiwan, 1,700 miles away from the epicenter.
“Earth shakes again, a bit larger than yesterday,” Dr. Qiwen Yao, an Australian researcher who is currently in Tsukuba, Ibaraki, said through instant messaging at 2:47 p.m., a minute before his Internet got cut off at 2:48 p.m. His mobile phone also lost connection shortly afterward. He is 203 miles away from the epicenter.
A tsunami warning was issued for many Pacific countries, going as far as Chile.
The Japan Meteorological Agency has issued a series of tsunami warnings and advisories, including major tsunami warnings for the east coast of Japan, where tsunami height is estimated to be 10 feet or more.
Additional reporting by Dao Yao and Yi Yang.
