MANILA - The Philippine Institute of Volcanology and Seismology (Phivolcs) on Monday maintained alert level 2 over Taal Volcano after it generated 252 volcanic earthquakes in the last 24 hours.

Under alert level 2, the volcano is seen to be under "increased unrest" as activities within the crater "indicate increased magmatic activity at shallow depths beneath the edifice," Phivolcs said in its 8 a.m. advisory.

"Sudden steam-driven or phreatic explosions, volcanic earthquakes, minor ashfall, and lethal accumulations or expulsions of volcanic gas can occur and threaten areas within the Taal Volcano Island," it said.

Last month, Phivolcs warned of Taal's possible eruption over a year since it last spewed ash and hot rocks, covering parts of Batangas, Cavite and Laguna with mud and grime.

• Phivolcs warns of possible Taal eruption, threat confined to volcano island

Towns surrounding the Taal Lake have been advised to "continuously assess and strengthen the preparedness of previously evacuated barangays around Taal Lake in case of renewed unrest," Phivolcs said.

Pilots were also told to "avoid flying close to the volcano as airborne ash and ballistic fragments from sudden explosions and wind-remobilized ash may pose hazards to aircraft," it said.

The Taal volcano last erupted on January 12, 2020 displacing 736,802 individuals and wrecking P3.40-billion worth of infrastructure and agriculture assets.

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