On Sunday April 4, 2010 the Sierra El Mayor Earthquake (Northern Baja California Earthquake) with magnitude M 7.2 and epicenter located in the Baja California region (N32.259°, W115.287°) occurred at 3:40pm local time. The event was shallow (10 km) and occurred along a strike-slip segment of the principal plate boundary between the North American and Pacific plates, in an area that coincides with the southeastern portion of the Laguna Salada fault system, a region with significant historical seismicity. The epicenter was 47 km SSE of Mexicali, Mexico and 51 km SSE of Calexico, California. Structural damage was observed in the regions of El Centro, Calexico, and Mexicali, extending southward along the regions in Mexico east of the fault.