A 7.4 magnitude earthquake occurred Tuesday along the southern coastline of Mexico.

The earthquake occurred at 10:29 a.m. local time (11:29 a.m. ET), with an epicenter located 11 kilometers southwest of Santa María Zapotitlán in Oaxaca state.

Earlier estimates put the magnitude of the earthquake at 7.7, but that has been revised down to 7.4 (and additional revisions are possible).

The Pacific Tsunami Warning Center said that hazardous tsunami waves are possible within 1,000 kilometers of the epicenter, including along the coasts of Mexico, Honduras, Guatemala and El Salvador.