Manila, Feb. 3 -- Daily frequency of earthquakes in Sultan Kudarat has been decreasing, but the public is advised to stay vigilant, the Philippine Institute of Volcanology and Seismology (Phivolcs) said on Tuesday.

"There is a general decreasing trend after the peak last Jan. 27 to Jan. 28, but this doesn't mean that (the series of earthquakes or swarm) has stopped," Phivolcs Director Teresito Bacolcol told the Philippine News Agency in an interview.

While there are days when the earthquake frequency is decreasing, Bacolcol noted that there is still a possibility that the seismic activity would rise.

"That is why, it is important to remain alert and prepared," he said.

The decreasing daily frequency is encouraging, but there is no gua...