A magnitude-6.5 earthquake shook eastern Japan off the quake-ravaged coast this morning, the US Geological Survey reported, prompting Japan to issue a tsunami alert.
There were no immediate reports of damage or injuries, but the Japan Meteorological Agency announced that a tsunami of up to 0.5m may wash into Miyagi Prefecture.
The tsunami alert was localised to Japan. The US Pacific Tsunami Warning Centre said no wave was expected in Hawaii or on the US west coast.
The alert was prompted by a quake that the US Geological Survey measured at 7:23am today (Japan time) near the east coast of Honshu.
The USGS said the quake was 5.9km deep.
A magnitude-9 quake off Japan's northeast coast on March 11 triggered a tsunami that barrelled onshore, triggering a humanitarian disaster that is thought to have killed about 18,000 people.
