Updated

A strong magnitude-6.8 earthquake struck central Chile on Saturday, but there were no immediate reports of injuries or damage.

The U.S. Geological Survey said the quake struck at 4:31 a.m. 29 miles southwest of the city of Ovalle, nearly 185 miles northwest of the capital of Santiago. It struck at a depth of 22 miles.

The quake shook Santiago, causing office buildings to sway. Chile's emergency services office first alerted, but later discounted, the possibility of a small tsunami.

Chile is highly earthquake-prone. In 2010, a devastating 8.8-magnitude quake struck the country, one of the strongest ever recorded. The quake and the tsunami it unleashed killed more than 500 people, destroyed 220,000 homes and washed away docks, riverfronts and seaside resorts.