A powerful magnitude-7.8 undersea earthquake strikes south of Japan leaving twelve people injured with minor injuries on Saturday.

As much as the residents of Japan hope not to experience another earthquake after its 2011 Tohoku earthquake experience, a magnitude 7.8 earthquake struck the country again and fortunately this time, there were no major casualties and no threat of tsunami.

According to BBC, the earthquake struck off the Ogasawara Islands 11:30 GMT on Saturday. The quake was reportedly centered on a remote spot in the Pacific Ocean, 874 kilometers (543 miles) from the Japanese capital, at a depth of more than 660 kilometers.

The said quake triggered short power outrage on the Shinkansen high speed train line between Tokyo and Osaka which caused the rest of the trains in the city an emergency stop for safety checks. Even Both runways at Narita Airport, the main international gateway to Tokyo, were temporarily closed for inspections.

"It shook violently. Our Buddhist altar swayed sideways wildly," Michiko Orita, a resident of the island of Hahajima, near the epicentre, told NHK national television.

The Saturday quake was then followed by a magnitude-6.4 earthquake the next day off Japan's Izu islands, which are located north of the Ogasawaras location. The latest struck had a depth of 8 miles with an epicenter located 390 miles southeast of Tokyo.

According to John Bellini of United States Geological Survey, the latest earthquake which stuck Japan was not strong enough to either trigger a tsunami warning or cause major damage. The Saturday temblor however, caused twelve reported victims who suffered minor injuries as a result of the falls.

It is known that Japan is one of the most seismically active countries in the world. In March 2011, a tragic and horrifying tsunami wiped off some of Japan's cities and provinces after a magnitude-9 earthquake struck the country. The quake left almost 16,000 people dead and caused nuclear meltdowns at the Fukushima Dai-Ichi nuclear power plant.