BEIJING - A series of earthquakes measuring at or above 6 on the Richter scale jolted off Japan's main Honshu island Saturday morning, according to the China Earthquake Network Center.

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The strongest quake among them measuring 6.3 on the Richter scale hit off the west of Honshu island at 2:59 am, the center said in a statement.

The epicenter, with a depth of 10 km, was monitored at 37 degrees north latitude and 138.5 degrees east longitude, the center said.

A massive 8.8-magnitude earthquake jolted the east coast of Japan's main Honshu Island at 1:46 pm Beijing Time Friday, causing hundreds of deaths and severe damage.