The magnitude-6.8 quake struck Friday at 2:36 p.m. local time and was centered about 185 miles northeast of Tokyo, Japan's Meteorological Agency said. The United States Geological Survey measured the earthquake at magnitude-6.3.
Japan's agency issued a tsunami advisory, predicting waves of 20 inches along the coast of Miyagi and Fukushima prefectures. The advisory was lifted about 30 minutes later.
The quake caused buildings in Tokyo to slightly sway. There were no immediate reports of injuries or damage.
This was the first sizeable quake in the area in over a month. In the weeks following the huge March quake, Japan was frequently rocked by aftershocks, including several stronger than magnitude 7.0. Their frequency and size have declined considerably.
Just over 20,000 people died or disappeared across Japan's northeastern coastline after the March earthquake and tsunami. Some 100,000 others were forced to evacuate their homes because of the threat of radiation from the crippled Fukushima Dai-ichi nuclear plant.
The Associated Press contributed to this story.
