TOKYO, June 20 (Xinhuanet) -- An earthquake with a preliminary magnitude of 5.0 rocked northeast Japan's Niigata Prefecture Monday afternoon, the Japan Meteorological Agency said.

    The region has been rattled by numerous quakes since an M6.8 earthquake last Oct. 23, which claimed the lives of 40 people. Monday's quake is considered to be a separate quake and not an aftershock, the agency said.

    The Niigata prefectural government and police said they have not received any reports of injuries or damage from the 1:03 p.m. (0403 GMT) quake. No tsunami warning was issued.

    The agency initially put the magnitude of the quake at 4.9 but revised it later to 5.0.

    The quake measured a 4-lower 5 on the Japanese seismic intensity scale of 7 in the prefecture, the agency said, adding that the epicenter of the quake was about 15 kilometers underground in the region. Enditem