Manila, Jan. 23 -- A series of weak to moderate earthquakes or seismic swarm affecting parts of Sultan Kudarat could continue for days or even weeks, the Philippine Institute of Volcanology and Seismology (Phivolcs) said Friday.

From 10:52 p.m. Jan. 19 to 6 a.m. Jan. 23, a total of 765 were recorded around Kalamansig, Sultan Kudarat.

At least 234 of these, with magnitudes ranging from 1.4 to 5.2, were plotted or located.

Phivolcs Director Teresito Bacolcol said the swarm was generated by the Cotabato Trench, noting that such activity reflects the gradual release of built-up stress in a tectonically active area.

Swarm indicates gradual release of stress in a tectonically-active area, he said in an interview with the Philippine News Age...