According to the US Geological Survey (USGS), the quake was at a depthof 38km with epicentre in the Sulu Sea, about 205km northwest of thesouthern port city of Zamboanga.
There were no immediate reports of damage or casualties, and no tsunami warning was issued.
The Philippines lies in the Pacific "Ring of Fire," where earthquakes and volcanic activities are common.
A magnitude-7.7 quake killed nearly 2,000 people on the northern island of Luzon in 1990.-VNA