Local reports on Twitter suggest strong shaking. There was earlier shaking today at a magnitude 4.9 but that appears it was just a tremor setting up for this earthquake.

An earthquake of 8.0 in Mexico 1985 killed at least 5000 people, it was located 350 km away.

The epicenter of this one appears to be closer to Oaxaca’s pacific coast, centered near Asunción Tlacolulita.

Update: The USGS early estimate is magnitude 7.7 (then updated to 7.4)