MEXICO CITY -- Authorities say a strong earthquake has struck well off the Pacific coast of western Mexico. There are no immediate reports of damage or injuries, and no tsunami is expected.

 

   The U.S. Geological Survey says Thursday's quake had a magnitude of 6.6 and was centered about 134 miles (215 kilometers) southwest of the town of Tomatlan, in Jalisco state. It struck beneath the ocean floor at a depth of 6.2 miles (10 kilometers).

 

   Jalisco's Civil Protection agency said via Twitter that it was monitoring the state's 125 municipalities to rule out any damage.

 

   The U.S. National Weather Service's Pacific Tsunami Warning Center said the quake was not forecast to cause a tsunami.