Courtsy msnbc
Tsunamis 20 inches tall hit some coastal regions
A strong earthquake jolted northwestern Japan on Monday morning and caused buildings in the capital Tokyo to sway. The Meteorological Agency said small tsunamis as high as 20 inches were believed to have hit coasts in the area.

Three nuclear reactors in the region automatically stopped but no irregularities were reported, public broadcaster NHK said.

The quake had a preliminary magnitude of 6.6 and was centered off the coast of the prefecture (state) of Niigata, the agency said in a statement. The tidal waves were believed to have hit the Niigata coasts, the agency added.