MANILA - The Philippine Institute of Volcanology and Seismology (Phivolcs) said Tuesday there was no cause for alarm for 4 active volcanoes in an abnormal condition following a strong earthquake that struck Masbate province.

Speaking to ABS-CBN's Teleradyo, Phivolcs Director Renato Solidum said the Taal Volcano in Batangas, Mayon Volcano in Albay, Bulusan Volcano in Sorsogon and Kanlaon Volcano in Negros Oriental had been under alert level 1 in the past few weeks.

"Kasi minsan naga-associate ang mga tao kahit malayo na po. Nonetheless, everytime na mayroong malaking earthquake, we actually monitor closely 'yung nearby volcanoes," he said.

(Sometimes people make the association [between volcanic activity and earthquakes] even if the quake happened far from the volcano. Nonetheless, everytime there's a major earthquake, we actually monitor nearby volcanoes.)

Solidum also dispelled concerns about the recent steam emission in Taal Volcano, videos of which circulated on social media.

The weak emission of white steam-laden plume that rose 20 meters in the Taal Volcano is normal, he said. In the past 24 hours, the volcano recorded 5 volcanic earthquakes.

Meanwhile, Phivolcs advised the public to refrain from entering the 6-kilometer radius permanent danger zone around the Mayon Volcano "due to the perennial life-threatening dangers of rockfalls, landslides or avalanches at the middle to upper slope, sudden ash puffs and steam-driven or phreatic eruptions from the summit."

During the 24-hour observation period, the volcano's monitoring network recorded a rockfall event.

An abnormal condition also prevails over Bulusan Volcano. Entry into the 4-kilometer radius permanent danger zone is strictly prohibited, the agency said.

Those within the 2-kilometer extended danger zone on the southeastern sector must be vigilant "due to the increased possibilities of sudden and hazardous phreatic eruptions."

In Negros Oriental, Kanlaon Volcano remains under alert level 1 and "has entered a period of unrest," Phivolcs said.

In the past 24 hours, the volcano recorded 4 volcanic earthquakes while moderate emission of white steam-laden plumes that rose 500 meters was observed.

Early Tuesday morning, a 6.6-magnitude earthquake shook Cataingan town in Masbate, killing a retired policeman and leaving dozens injured.

• 1 dead, several injured in Masbate quake epicenter

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