By DPA,

Tokyo : A magnitude-6.8 earthquake hit northern Japan Wednesday night, the Japan Meteorological Agency said. No tsunami warnings were issued.

Several people were taken to a hospital in northern city of Aomori, but all sustained only minor injuries, according to media reports.

There was no damage reported to nuclear power plants in Miyagi province, and these continued operating. Immediately after the quake, the government set up a task force at prime minister's office.

The agency said the quake's epicentre was located about 120 km under the sea basin off the northeastern coast of Iwate province.