An early 6.8-magnitude earthquake shaken the northeastern Japan on Wednesday March 14^th as the U.S. Geologycal Survey reported. At the same time, the Japanese Meteorological Agency issued a brief tsunami advisory, warning of a half-meter wave. Later officials reported that a small tsunami, 20 centimeter wave struck around 210 kilometers off the northern island of Hokkaido which was followed by a 10-centimeter wave that hit land later.

The quake was centered about 270 kilometers (170 miles) off the east coast,and according to police no immediate damages were reported. The waves hit two locations in Aomori prefecture, which was one of the areas in Japan's northeast devastated by last year's disaster.

The agency had initially said a tsunami could be as high as 50 centimetres, but U.S. monitors said there was no Pacific-wide tsunami threat.

The quake struck at a relatively shallow 10 kilometres below the seabed at 6:09 p.m. local time, and it came just three days after the one-year anniversary of the earthquake and tsunami that killed thousands in Japan, and triggered the world's worst nuclear crisis in a quarter century.