A strong earthquake has struck in the Pacific off central Chile, but authorities say there are no reports of injuries or serious damage.

The U.S. Geological Survey says the quake had a preliminary magnitude of 6.9 Tuesday night. It says the epicenter was about 54 miles (88 kilometers) northwest of the coastal city of Coquimbo at a depth of 6 miles (10 kilometers).

The government's emergency office says it has no reports of injuries or damage. Chile's navy says the quake didn't have the conditions for generating a tsunami.

Chile is prone to earthquakes. In 2010, it was shaken by an 8.8-magnitude quake, one of the strongest ever recorded. The quake and tsunami it caused killed more than 500 people, destroyed 220,000 homes and washed away docks and seaside resorts.