The magnitude-8.1 quake, which was felt as far as Mexico City and Guatemala City, was registered off Mexico's southern coast just as heavy rains from Hurricane Katia lashed the east. The epicenter was in the Pacific Ocean, some 600 miles (1,000 kilometers) southeast of the capital and 74 miles (120 kilometers) from the Pacific coast.
Mexican President Enrique Peña Nieto said the quake was the strongest earthquake Mexico has experienced in 100 years.
It hit just before midnight on Thursday, when many people would have been sleeping.
Alejandro Murat, the governor of Oaxaca, told CNN that 23 people were killed in his state alone. Four others have died in Chiapas state and two in Tabasco.
The states of Chiapas, which borders Guatemala, and Oaxaca were closest to the quake. Peña Nieto said three people died Chiapas and two in Tabasco. Multiple homes in Chiapas collapsed, Peña Nieto said.
-- Four people may be trapped inside a collapsed hotel in Oaxaca, Oaxaca Civil Protection Director Amado Bohorquez told CNN.
-- The United States Geological Survey (USGS) Pager system, which predicts economic and human loss after earthquakes, issued a red alert. "High casualties and extensive damage are probable and the disaster is likely widespread. Past red alerts have required a national or international response," it said.
-- A tsunami was confirmed in Mexico, with one wave coming in at 3 feet (1 meter), according to a tweet from the National Weather Service's Pacific Tsunami Warning Center. It said tsunami waves taller than 10 feet (3 meters) could hit coast of Mexico, while 3-foot waves could reach as far as Ecuador, New Zealand and Vanuatu. Read More