Japan earthquake update: 6.7 earthquake hits off coast of Japan, no tsunami warning

A minor tsunami hit northern Japan today after a strong undersea earthquake struck off the coast, in the same area that was devastated by a killer tsunami in 2011, Japan's meteorological agency said.

The national meteorological department said the epicenter of the quake was located in the ocean, some 210 kilometers away from the town of Miyako in Iwate Prefecture. Its seismic focus was identified at the depth of about 10 kilometers below the seafloor.

Tuesday's quake, which had a preliminary magnitude of 6.9, was the 830th aftershock of magnitude 5 or higher, according to the agency's website. Around 300 of those occurred within two days of the main earthquake on March 11, 2011.

One of the hardest-hit districts was the town of Hashikami, where upper-5 was recorded. It registered as 5-weak in the village of Fudai in Iwate Prefecture.

"here were no immediate reports of damage or injuries. "We are using the emergency broadcast to advise people to keep away from the sea ... the quake was pretty strong and lasted a long time so I thought there would be a tsunami warning," Kozo Hirano, an Otsuchi Town official in Iwate, told NHK.

The quake hit at 8:06 a.m. It measured 4 on the Japanese seismic intensity scale of 7 in Iwate and three other prefectures in Tohoku - Aomori, Akita and Miyagi.

Tohoku Electric Power corporation said the quake had not affected the operations of nuclear plants.

"We are using the emergency broadcast to advise people to keep away from the sea," Kozo Hirano, an Otsuchi Town official in Iwate, told Japan's public broadcaster NHK.

"The quake was pretty strong and lasted a long time so I thought there would be a tsunami warning."