A moderately explosive eruption of Mount Kanlaon on Thursday morning sent volcanic ash as far as Cebu, blanketing communities in Negros Island and western Cebu, forcing class suspensions, disrupting flights and prompting authorities to step up emergency response measures.

The Philippine Institute of Volcanology and Seismology (Phivolcs) said the eruption began at 7:33 a.m. and lasted three minutes, producing a dark gray ash plume that rose two to three kilometers above the summit before drifting east.

The eruption also generated pyroclastic density currents that descended the volcano’s southeastern slopes to within about a kilometer of the crater, based on observations from the Upper Pantao monitoring station.

Phivolcs said its monitoring network recorded 14 volcanic earthquakes and one explosion-type earthquake during the 12-hour monitoring period ending at noon Thursday.

Resident volcanologist Mari-Andelyne Quintia said ashfall was immediately reported in Canlaon City and one barangay in San Carlos City, Negros Occidental.

Residents posted photos and videos showing light to moderate ashfall coating homes, roads, farms and public markets. In Barangay Mabigo, vegetables being sold at the upland market were covered by volcanic ash, causing damage to produce.

24/7 monitoring

Ashfall was also reported in the barangays of Binalbagan, Malaiba, Mabigo, Pula, Lumapao, Bayog, Panubigan, Aquino, and parts of Linothangan and Masulog.

“Our monitoring has been conducted 24/7 ever since. We are further intensifying it because there is current major activity at Mount Kanlaon,” Quintia told the DAILY TRIBUNE.

The Canlaon City government immediately distributed face masks to residents as ash continued to fall across affected communities.

The ash cloud later reached Cebu, where authorities reported ashfall in Toledo City and the municipalities of Balamban, Pinamungajan, Asturias, Aloguinsan and Tuburan.

Light ashfall was also reported in Metro Cebu, including Cebu, Mandaue, Lapu-Lapu, Talisay and Naga cities, as well as several neighboring municipalities.

The ashfall prompted local governments to suspend classes in affected areas.

The Cebu Provincial Disaster Risk Reduction and Management Office said it had begun distributing 6,500 N95 face masks, including 500 for Toledo City and 6,000 for western Cebu municipalities.

Masks recommended

The provincial government also placed hospitals under heightened alert, while the Department of Health advised residents to remain indoors whenever possible, wear properly fitted N95 or KN95 masks when going outside, keep doors and windows closed, protect food and water supplies, and monitor official advisories.

Operations at Mactan-Cebu International Airport were also affected after volcanic ash was detected on airport grounds, forcing the cancellation of seven departing flights and one arriving flight.

“Volcanic ash is highly abrasive and poses a severe risk to aircraft engines, exterior surfaces and navigational instruments,” airport authorities said.

Phivolcs maintained Alert Level 3 over Kanlaon, indicating magmatic unrest and the possibility of further short-lived explosive eruptions.

Authorities reiterated that entry into the volcano’s six-kilometer Permanent Danger Zone remains strictly prohibited because of the continuing threat from ashfall, ballistic fragments, pyroclastic density currents and other volcanic hazards.