It says the quake was centered about 25 miles (40 kilometers) southwest of Puerto Quellon and at a depth of 20 miles (33 kilometers).
Chilean officials have declared a preventative tsunami alert.
Chile's national emergency office has issued an alert and ordered the evacuation of coastal areas of Los Lagos region, reported BBC.
"As a measure of precaution, we order the evacuation of coastal areas of Biobio, Araucania, Los Rios, Aysen," the alert said.
(More details awaited)