It hit 94 km (58 miles) south of the city of Ambato at a depth of 112 km (69 miles), the USGS said.
The quake knocked down power cables, leaving the areas of Puertas Negras, Guano and Chunchi without electricity, Ecuador’s Risk Management Secretariat said in a statement. There was slight damage to homes and landslides hit a road, it said.
One person suffered a broken bone in the town of Babahoyo and authorities were assessing whether any houses had collapsed, the secretariat said.
Tremors were felt in the capital, Quito, and in the industrial port city of Guayaquil, where people ran into the streets, a Reuters witness said.
Ecuador’s geological institute said the earthquake, which hit a remote area with a low population, caused five smaller aftershocks.
The Andean nation has frequent seismic activity. In 2016, a devastating 7.8-magnitude earthquake struck Ecuador’s Pacific coast, killing more than 650 people.
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