A powerful earthquake struck Mexico's southern Oaxaca region on Tuesday, killing at least five people and shaking buildings hundreds of miles away.

The 7.4-magnitude quake struck mid-morning, according to the U.S. Geological Survey. Its epicenter was off the Pacific coast about seven miles southwest of Santa María Zapotitlán, near the beach resort of Huatuco.

Reuters reports that rockfalls blocked the mountain roads in the region, cutting off isolated villages.

The state-run oil company Pemex said one of its workers fell from a refinery structure to his death, and the quake caused a fire at its facility in the city of Salina Cruz.

Mexican President Andrés Manuel López Obrador said 147 aftershocks had been reported by noon.

The quake was felt in several states and triggered seismic alarms in Mexico City, sending residents there onto the streets.

This is not the first large earthquake to jolt the area in recent years. In September 2017, an 8.1 magnitude quake struck off the southern coast, killing at least 60 people. The U.S. Geological Survey said that Tuesday's earthquake was "near the northern end of the aftershock distribution" of the 2017 event.

NPR's Carrie Kahn contributed to this report.

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