The agency initially said the quake's magnitude was 7.5 but later revised it to 7.0.
The U.S. Geological Survey measured the magnitude at 7.2.
The quake struck at 12:32 p.m. (0332 GMT) at a depth of about 240 kilometers (150 miles), the Meteorological Agency said.
The agency said the epicenter was in the northernmost reaches of the island chain.
The islands lie along the Pacific Basin's "Ring of Fire," an arc of volcanos and fault lines where quakes are frequent.