Two earthquakes struck almost simultaneously off Japan's central coast late Friday, the Japan Meteorological Agency said. No tsunami warning was issued and no damage was reported.

The first quake, with a magnitude of 6.6, struck at 10:41 p.m. and was centered in the Pacific Ocean off Iwo Jima, about 930 miles south of Tokyo.

Another quake with a magnitude of 7.4 occurred off the Mariana Islands around the same time, according to the agency.

Slight shaking was reported in northeastern towns on Japan's main island of Honshu.

No injuries or damage were immediately reported. It was not immediately known whether the two quakes were related.

Japan is one of the world's most earthquake-prone countries and sits atop four tectonic plates.