At least 32 people were killed as Mexico was hit by the most powerful earthquake in a century that struck off the nation’s Pacific Coast late on Thursday, rattling millions of residents with its violent tremors and triggering a series of tsunami waves.

The quake hit offshore in the Pacific at 11.49 p.m. (0449 GMT), about 100 kilometres from the coastal town of Tonala, in far southern Chiapas state, Mexico’s seismologic service said. A tsunami warning was issued for Mexico, with three-metre-high waves possible, and other nearby countries.

The epicentre of the earthquake was off the coast of Chiapas, a state in southern Mexico, but the rumblings rocked the Mexican capital more than 600 miles away, causing electricity failures, and reports of sporadic damage, the New York Times reported.

Mexican President Enrique Peña Nieto said the quake measured 8.2 and was the strongest earthquake Mexico has experienced in 100 years whereas the US Geological Survey put the magnitude at 8.1.

About 50 million people across the country felt the earthquake. The force sent residents of the megacity fleeing into the streets at midnight, shaken by the alarms blaring over loudspeakers and a full minute of tremors.

Windows broke, walls collapsed, and the city seemed to convulse in terrifying waves. The quake even rocked the city’s landmark Angel of Independence monument. The effects in the southern states of Chiapas and Oaxaca were probably more severe.

Alejandro Murat, the Governor of Oaxaca, told the Televisa network that at least 23 people had died in the state, and local officials said residents were buried under the rubble of buildings.

Luis Manuel García Moreno, the secretary of civil defence for the state of Chiapas, said the toll there had risen to seven, and two children died in the state of Tabasco, one when a wall collapsed, the other after a respirator lost power in a hospital.

The effects were also felt in Guatemala, where at least one person died and homes along the border with Mexico were levelled. Many people sustained injuries in the 7.3 magnitude quake that hit the country just hours after the one in Mexico.

Schools in at least 10 Mexican states were ordered closed on Friday as the President ordered an immediate assessment of the damage nationwide. In the hours after the quake, the National Seismological Service registered several aftershocks.

“We are assessing the damage, which will probably take hours, if not days,” said Nieto, who addressed the nation just two hours after the quake. “But the population is safe over all. There should not be a major sense of panic.”

Mexico is situated near several boundaries where portions of the earth’s crust collide. The quake was more powerful than the one that killed nearly 10,000 people in 1985.

Mexican authorities alerted the coastal states of Oaxaca and Chiapas of the possibility of destructive waves of higher than 13 feet.

The US Tsunami Warning System said hazardous tsunami waves were possible on the Pacific coasts of Guatemala, El Salvador, Costa Rica, Nicaragua, Panama and Honduras within three hours.

The quake comes a few days before the anniversary of the earthquake of September 19, 1985, that killed over 40,000 people in Mexico City.

At least 12 aftershocks with tremors measuring above 5.0 in magnitude and a fifth at 4.9 were recorded and some 23,000 people likely experienced the violent shaking, according to the US Geological Survey.