The alert level for a Philippine volcano was raised Monday after an “explosive eruption” sent a plume of ash, gas and steam five kilometers (three miles) into the sky, the volcanology agency said.

Mount Kanlaon on the central island of Negros erupted shortly before 7 p.m. (1100 GMT), prompting warnings for nearby residents to wear facemasks due the threat of volcanic gases and falling ash.

“When it erupted we heard a thunder-like sound,” Ethan Asentista-Khoo, 35, told AFP from his home in Pula village near the volcano.

“There was like a fire on the mouth of the volcano, which lasted around one to two minutes. I didn’t see any lava or rocks coming out.”

The Philippines is located in the seismically active Pacific “Ring of Fire” that hosts more than half of the world’s volcanoes.

Kanlaon is one of 24 active volcanoes in the archipelago nation.

Eruptions can be deadly, with pyroclastic and lahar flows as well as ashfall posing hazards to communities surrounding the volcano.