At least 12,800 people have been evacuated from the area around the mountain as volcanic activity intensified.
Mayon, the most active volcano in the Philippines, has begun to send lava down its slopes, with increased volcanic activity in an area home to tens of thousands of mostly poor farmers.
Lava began appearing on the slopes of Mayon Sunday night, and Teresito Paculcol, director of the Philippine Institute of Volcanology and Seismology, said authorities were on alert for further developments.
“What we are seeing now is a heavy explosion,” Bakulkul told the Associated Press news agency. “We look at this on a daily basis.”
At least 12,800 people living within a 6-kilometer (3.7-mile) radius of Mayon volcano have been evacuated since last week. Pakulkul said there is potential for the high-risk area to expand if the eruption turns violent.
The area below Mayon, about 330 kilometers (205 miles) southeast of the capital, Manila, has been designated a permanent danger area, but several thousand people still live there because they have nowhere else to go.
Volcanologists say the lava is another sign of increased activity, noting that there have also been about 260 rockfall events in the past 24 hours, compared to 177 in the previous 24 hours. More tremors were also recorded – 21 in the past 24 hours compared to two previously.
Sulfur dioxide emissions also tripled on Saturday, according to state volcanologists.
“There are health risks associated with approaching the eruption due to inhalation of sulfur dioxide gas or falling ash particles,” Health Minister Teodoro Herbrosa told a news briefing on Sunday.
The volcano alert level remains at three in the five-step system in the Philippines, which means there is a trend towards a dangerous volcanic eruption in weeks or days.
Albay province, where the Mayon Cone is a popular tourist attraction, was placed under a state of emergency on Friday to allow faster distribution of any relief funds in the event of a major eruption.
Mayon is one of 24 active volcanoes in the Philippines, and last erupted in 2018, displacing tens of thousands of villagers.
The archipelago sits on the Pacific Ocean’s so-called “Ring of Fire”, the edge of seismic faults where most of the world’s earthquakes and volcanic eruptions occur. It also sees frequent hurricanes and tropical storms, with a typhoon expected to hit the region later this week.
The country’s most powerful eruption in recent decades was Mount Pinatubo in 1991, which killed more than 800 people and produced an ash cloud that traveled thousands of kilometers.
“Infuriatingly humble analyst. Bacon maven. Proud food specialist. Certified reader. Avid writer. Zombie advocate. Incurable problem solver.”