TOKYO (February 2, 2013)--A strong earthquake struck Japan's northern island of Hokkaido Saturday, but authorities said there was no danger of a tsunami and there were no immediate reports of injuries or damage.

Japan's Meteorological Agency said the quake had a magnitude of 6.4 and hit at 11:17 p.m. Saturday in the Tokachi region in southern Hokkaido, at a depth of 75 miles.

The agency said there was no danger of a tsunami from the quake.

The U.S. Geological Survey said the quake's magnitude was 6.9.

Japanese public broadcaster NHK reported nearby nuclear power plants, including Tomari and Higashidori, which are currently idled for safety inspections, reported no abnormalities.