Japan's quake-devastated northeast was hit by another strong earthquake of 7.4 magnitude and the authorities issued fresh tsunami warning for the northeastern coast, the area already badly hit by the 11 March earthquake and tsunami.
The underwater quake, which hit 66 km off the east of Sendai, a city severely impacted by the 11 March quake and tsunami, jolted the Miyagi prefecture, 118 km north of Fukushima and prompted an immediate tsunami alert.
The quake was felt as far away as Tokyo and Japan's national broadcaster NHK announced warning that the it could trigger tsunami waves up to three feet high.
The authorities asked those in the quake-hit areas to evacuate to higher ground.
However, no casualties were reported from the area or nearby.
The Hawaii-based Pacific Tsunami Warning Center had earlier ruled out the possibility of an ocean-wide tsunami.
TV footage from broadcaster NHK showed that power was off in parts of Sendai. The broadcaster also reported gas and water leaks in some areas of the city.