The U.S. Geological Survey is reporting that another major earthquake has hit northwestern Japan -- the same region affected by March's devastating quake and tsunami.
There have been no reports of any injuries or damage and no tsunami warning is in effect.
The U.S.G.S. says the preliminary magnitude of 6.4 struck at 3:53 a.m. Sunday in the Pacific Ocean.
It struck approximately 18 km east-southeast of Iwaki on Honshu Island. The depth was 43.5 km with the epicentre 184 km northeast of Tokyo.
About 23,000 people were killed or left missing across Japan's northeast coastline after March's catastrophic earthquake and tsunami.
The Fukushima Dai-ichi nuclear plant was severely crippled by the disasters, resulting in a severe radiation threat to the region.
Meanwhile, record rains have also caused massive flooding in northwestern Japan Saturday. At least one person is dead and five others are missing. Local media reported that the government has ordered evacuation for nearly 400,000 citizens in the affected areas.
With files from The Associated Press