A magnitude-6.1 earthquake shook the southern Philippine island of Mindanao early Saturday, without the authorities reporting any victims or declaring a tsunami alert.

Officials at the Philippines emergency management office said they have not been notified of any deaths or significant damage, adding that the temblor had occurred at a very great depth.

The U.S. Geological Survey, which measures seismic activity around the world, located the seismic focus at 38.1 kilometers (23.7 miles) deep in the ocean off the coast of Surigao del Sur province.

One person died on Aug. 31 in a magnitude-7.6 quake that rattled Mindanao and led the Pacific Tsunami Warning Center to declare an alert for a giant wave.

The Philippines is located on the Pacific Ring of Fire, an area of great seismic and volcanic activity that is shaken by some 7,000 earthquakes a year, mostly of moderate intensity.

Temblors above magnitude-5 occur sporadically in southern Mindanao, Batanes and the eastern region of Bicol. EFE