MANILA - State seismologists on Tuesday raised alert level 2 over Taal Volcano which warns of probable magmatic activity that may or may not lead to an eruption.

Under alert level 2, the second-lowest in a 5-step system, evacuation is not yet recommended but the public is reminded that Taal Volcano Island is a permanent danger zone and entry must remain strictly prohibited, Phivolcs said in its 8 a.m. bulletin.

"Local government units are advised to continuously assess previously evacuated barangays around Taal Lake for damages and road accessibilities and to strengthen preparedness, contingency, and communication measures in case of renewed unrest," it said.

"Residents of these barangays are advised to be always prepared, to keep calm and listen to information only from trusted or verified sources."

"Civil aviation authorities must advise pilots 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.

Some 28 volcanic tremor episodes were recorded in the past 24 hours, totaling 866 since the onset of increased activity on February 13, Phivolcs said.

Residents who returned to the volcano island following its eruption last year were evacuated 3 days later as Phivolcs raised alert level 1.

• Batangas residents evacuated over Taal Volcano's 'increased activity'

"Overall, seismic activity in the past month indicates increased magmatic and hydrothermal activity at shallow depths beneath Taal Volcano Island," it said.

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