The US Geological Survey said the quake struck shortly before 8:00 am near Acapulco, a major port and beach resort.

It was felt around 400 kilometers (250 miles) away to the north in Mexico City, where alarms sent people rushing into the street for safety, disrupting a holiday weekend.

A 60-year-old man died after falling while evacuating his second-floor apartment in the capital, local authorities said.

Twelve others were injured, city Mayor Clara Brugada wrote on social media, but there were no reports of major damage in the country's largest city.

President Claudia Sheinbaum was forced to evacuate the presidential palace during her regular morning press conference.

Mexico's National Seismological Service said that the earthquake's epicenter was situated 14 kilometers southwest of the town of San Marcos in the state of Guerrero.

Sheinbaum said there were no immediate reports of major damage, but in San Marcos, the effects were visible.

A woman in her fifties "lost her life when her house collapsed on top of her," said Guerrero Governor Evelyn Salgado.

San Marcos Mayor Misael Lorenzo Castillo said around 50 houses were destroyed and "all the houses have cracks."

Residents showed an AFP journalist the cracks in the walls of their homes and sections of collapsed walls.

"San Marcos has been badly affected, devastated," lamented Rogelio Moreno, a resident, standing in front of his damaged home.

- 'Woke in terror' -

Mexico is situated between five tectonic plates and as such is one of the world's most seismically active countries.

Karen Gomez, a 47-year-old office worker living on the 13th floor of an apartment building in Mexico City, told AFP she was roused from her sleep by a street siren.

"I woke up in terror. My cellphone alert said it was a powerful earthquake."

Norma Ortega, a 57-year-old kindergarten director, living in a 10th-floor apartment, said she could feel her building shake.

In Acapulco, Ricardo, a tourist from the central Mexican state of Morelos, fled his hotel shirtless after sirens sounded.

The center of Mexico City is built on the muddy subsoil of what was once the bed of a lake, making it particularly vulnerable to earthquakes.

- Loudspeakers on lampposts -

The quakes most strongly felt usually originate off Guerrero state on the Pacific coast.

On September 19, 1985, an 8.1-magnitude earthquake devastated a vast swathe of Mexico City, leaving nearly 13,000 dead, mostly in the city, according to official figures.

In 2017, also on September 19, a 7.1-magnitude quake killed 369 people, also mostly in Mexico City.

Early warning systems, including smartphone apps, have been developed to warn citizens strong quakes and urge them to reach safety.

Mexico City has also installed loudspeakers on lampposts to broadcast the alerts.