MANILA, Philippines – (UPDATE 2) Two earthquakes shook the southern Philippines Saturday but neither one was strong enough to cause casualties or damage.

The Philippine Institute of Volcanology and Seismology said the first tremor, which had a magnitude of 5.8, struck at 3:51 a.m., with its epicenter located some 85 kilometers east southeast of General Santos City. It was tectonic in origin and occurred 151 km below the earth’s surface.

It was felt at Intensity 3 in Davao City, Intensity 2 in General Santos City and Intensity 1 in Kidapawan City.

A weaker quake struck 146 kilometers east northeast of Mati, Davao Oriental with a magnitude of 3.7 more than seven hours later at 11:14 am.

The quake's depth was shallower at 33 kilometers and was also tectonic in origin.

It was was felt at Intenstiy 2 in Hinatuan, Surigao del Sur, Philvocs said.

The Philippines lies in a region called the Pacific Ring of Fire that is known for a high degree of volcanic and seismic activity due to the meeting of various continental shelves in the area.