TOKYO, April 9 (Xinhua) -- A 6.1-magnitude earthquake struck Shimane Prefecture in western Japan on Monday morning, injuring four people in one of the hardest-hit areas, local media reported.

According to the Japan Meteorological Agency (JMA), the temblor occurred at 1:32 a.m. local time (1632 GMT Sunday), with the epicenter at a latitude of 35.2 degrees north and a longitude of 132.6 degrees east and at a depth of 10 km.

The quake, revised upward from a preliminary magnitude of 5.8, logged upper 5 in the city of Oda in western Shimane and lower 5 in some other areas of the prefecture on the Japanese seismic intensity scale which peaks at 7.

According to local officials, among the injured was a teenage boy from Oda City who fell from his bed as a result of the quake.

Parts of the city also experienced a power outage and had the water supply cut, causing the local government to call on a Self-Defense Forces unit to provide assistance.

The powerful quake caused some cracks in buildings and roads, local media reported, but all nuclear power stations in the region were functioning as normal and no tsunami warning was issued.