Japan Earthquakes Strong Enough To Rattle Tokyo Buildings

Channel News Asia reports that a strong earthquake shook Japan early Thursday:

A strong earthquake measuring 6.3 on the Richter scale shook the Tokyo region early Thursday, Japan's weather agency said.

There were no immediate reports of damage and no tsunami alert was issued...

...The earthquake, which struck at a depth of 20 kilometres, was powerful enough to rattle buildings in central Tokyo.

Here is a map of the region from the U.S. Earthquake Center, which shows that there were several other quakes.