(PNA file photo)

MANILA -- The Philippine Institute of Volcanology and Seismology (Phivolcs) on Wednesday afternoon said increased activity has been observed anew in Mount Bulusan.

In an advisory issued at 5 p.m., Phivolcs said 213 volcanic earthquakes were recorded since 5 a.m. of June 24.

The strongest of these quakes caused by movements or eruptions of magma from the volcano was magnitude 3.5 recorded at 11:27 p.m. of June 24. This quake was felt at Intensity III in the municipalities of Irosin and Bulusan, Sorsogon.

At 1:39 p.m. Wednesday, a magnitude 2.3 imperceptible (not felt) volcanic quake was also recorded.

Both volcanic quakes were located on the south-southeastern flank of Bulusan edifice, and approximately 3 kilometers deep.

Phivolcs warned of the possibility of a renewed eruptive activity from the Bulusan summit and potentially from the vents of its southern sides.

The volcano is still under Alert Level 1 (low-level unrest).

Those living within valleys and along river/stream channels, especially on the southeast, southwest and northwest slopes of the volcano edifice, should be vigilant against sediment-laden stream flows and lahars during heavy and prolonged rainfall.

Phivolcs also reminded local government units and the public that entry into the 4-kilometer radius permanent danger zone must be strictly prohibited, and that vigilance in the 2-kilometer extended danger zone on the southeast sector must be exercised due to the increased possibilities of sudden and hazardous phreatic eruptions. (PNA)