An earthquake measuring 5.8 on the Richter scale Monday jolted areas in the Niigata Prefecture in northern Japan which had been hit by a series of strong earthquakes since late October, the Japan Meteorological Agency reported.

The 11:16 a.m. (0216 GMT) quake measured upper 5 on the Japanese seismic intensity scale of 7 in the Uonuma city's Sumon district in central Niigata Prefecture, the agency said.

There were no immediate reports of injuries or damage from the quake. Nor tsunami warning has been issued.

Niigata has suffered three major quakes and hundreds of minor ones since Oct. 23. Since the first quake, the agency has warned against more major aftershocks as high in grade as 6.

So far, 38 people have died from the earthquakes and such aftereffects as stress, overfatigue and economy class syndrome.

Source: Xinhua