GUASAVE, Mexico The U.S. Geological Survey initially reported the magnitude of the quake as 6.9, but later in the day revised it to 6.7.
The tremor struck at 11:53 a.m. (10:53 a.m. PT) about 72 miles south of Los Mochis, a city just inland from the coast in Sinaloa. It was at a relatively shallow depth of 6.2 miles.
There were no immediate reports of any damage or injuries.
The same region was hit by three moderately powerful earthquakes
ranging in magnitude from 5.5 to 5.8 Tuesday night and early
Wednesday, but they caused no known damage.
The Associated Press contributed to this story.