A magnitude 7.8 earthquake has struck 194 kilometers off Japan's coast, according to United States Geological Survey (USGS), but there were no immediate reports of damage, according to ABC News.

The quake, which hit off Japan's Bonin Islands, reportedly rocked buildings in Tokyo as it built in intensity about 8:30pm local time.

The Pacific Tsunami Warning Center said: "There is no tsunami threat because the earthquake is located too deep inside the earth."

The USGS reported the epicenter was approximately 874 kilometers south of Tokyo in the Pacific Ocean, while the Japan Meteorological Agency said the earthquake had a magnitude of 8.5 at a depth of 590 kilometers.

Tokyo Electric Power Company said there were no abnormalities at the crippled Fukushima nuclear power plant following the quake.

The runways at Tokyo's Narita airport were operating normally but the high-speed bullet train service between Tokyo and Osaka was halted due to a power outage, according to public broadcaster NHK.