MANILA -- The Kanlaon volcano in central Philippines erupted Monday evening, spewing a column of ash and gas that rose to 5,000 meters, the Philippine Institute of Volcanology and Seismology said.

"The explosive eruption produced a voluminous and incandescent plume that rapidly rose to 5,000 meters above the vent and probable pyroclastic density currents approximately 2 to 3 km down the southern and southeastern slope," the institute said.

The institute noted that coarse ashfall and sulfurous odors have been reported in communities on the volcano's western slopes.

The eruption, which occurred at 6:51 pm local time and lasted six minutes, caused the institute to raise the alert level from 1 to 2 due to the volcano's "increasing unrest," which means the current unrest "could eventually lead to further explosive eruptions or even precede hazardous magmatic eruption."

The institute urged the people to be vigilant and avoid the four-km danger zone due to the risks of sudden explosions, rockfalls, and landslides. It also advised pilots to avoid flying close to the summit due to the danger posed by the ash to aircraft.

Kanlaon straddles the provinces of Negros Oriental and Negros Occidental. It is the highest mountain on the island of Negros, with an elevation of 2,465 meters above sea level. The active stratovolcano last erupted in December 2017.