A series of moderate earthquakes ranging from magnitude 4.4 to 5.3 shook the waters off Davao Occidental early Sunday, according to the Philippine Institute of Volcanology and Seismology (Phivolcs).
The strongest tremor, measuring magnitude 5.3, was recorded at 1:22 a.m. It was located 217 kilometers south 70° east of Jose Abad Santos, Davao Occidental, at a depth of 52 kilometers.
Less than 30 minutes later, at 1:51 a.m., a magnitude 4.8 quake struck 41 kilometers south 52° east of Jose Abad Santos, with a depth of 55 kilometers.
Another tremor, magnitude 4.4, was monitored at 3:29 a.m., about 447 kilometers south 64° east of Sarangani Island, at a depth of 35 kilometers.
Phivolcs said the earthquakes were tectonic in origin. No tsunami warning was issued.
As of posting time, local authorities have reported no damage or casualties.
The Philippines lies along the Pacific Ring of Fire, a region known for frequent seismic activity due to the movement of major tectonic plates.