MANILA- Filipinos living in the danger zone around the Taal Volcano should stay away until government advises them to return home, a state seismologist said Tuesday, as he warned that the volcano’s calmer appearance sometimes offers a false sense of security.

While people might sometimes notice a slowdown in Taal’s eruption, this should not be taken as a sign of lesser volcanic activity, Phivolcs director Renato Solidum said.

“Puwedeng masabi ninyo na mas mahina 'yung nangyayari at minsan ay nagiging false sense of security kaya pumupunta 'yung ibang tao at bumabalik. Hindi 'yan ang basehan namin bakit namin itinaas ang alert level 4,” he told reporters in Malacañang.

(You can sometimes say that there seems to be no more activity and this sometimes gives a false sense of security that’s why some people return but that’s not the basis for declaring an alert level 4.)

• Taal survivors haggle to check homes in volcano's danger zone

Taal Volcano has been under alert level 4—which warns of a “hazardous” eruption in the next “hours or days” after it spewed gray ash and steam last Sunday.

Thousands have since fled their homes as ash from the rumbling volcano blanketed Southern Tagalog provinces, with the gray shower even reaching Metro Manila and Central Luzon.

Solidum explained that earthquakes and reported fissures or cracks on the ground are signs of the volcano’s unrest, which should not be taken lightly.

“Ibig sabihin, umaakyat 'yung volume ng magma na puwede pa mag-supply doon sa eruption ng Taal,” he said.

(It means that the volume of magma is increasing which can supply the Taal Volcano’s eruption.)

There were reports of fissures in the towns of Agoncillo and Lemery in Batangas, Solidum said. The 2 towns are within the 14-kilometer radius from the volcano where people were told to leave.

Taal recorded a deadly eruption in 1911 when it killed 1,335 people with burning rocks, ash, and acid rain in a span of 3 days, data from Phivolcs showed.

It described the eruption as "very violent," characterized by the cracking of the ground and thick deposits of ashfall.

At least three violent eruptions were also recorded in the 1700s, with the total deaths undetermined.

Solidum urged the public to heed government instructions as he warned of a possible “hazardous explosive eruption.”

“We need the cooperation of everyone. 'Yung scenario ng hazardous explosive eruption is a real scenario. That has been exhibited by Taal Volcano,” Solidum said.

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