The Philippine Institute of Volcanology and Seismology (Phivolcs) reported an increase in seismic activity at Bulusan Volcano in Sorsogon province. Ninety-four volcanic earthquakes have been recorded since 3 a.m. Monday. The majority were weak, shallow volcano-tectonic earthquakes.
Four low-frequency volcanic earthquakes were also detected. These were produced by the movement of fluids. Phivolcs indicated the earthquakes originated within 20 km deep beneath the volcano.
Alert Level 0 remains in effect, but steam-driven eruptions are possible. The public is advised to avoid the 4-km radius permanent danger zone. Aviation authorities are warned of potential ash hazards.