Kanlaon Volcano, one of 24 active volcanoes in the Southeast Asian nation, has had several eruptions in the past century -- the most recent of which happened last month.

A level three alert -- out of a scale of five -- put in place during an eruption in December remained unchanged Tuesday, as officials highlighted an existing six-kilometer (four-mile) evacuation radius.

"A moderately explosive eruption occurred at the summit crater of Kanlaon Volcano at 2:55 am today (1855 GMT Monday)," the Philippine Institute of Volcanology and Seismology said in a statement, adding that it lasted five minutes.

"The eruption generated a greyish voluminous plume that rose approximately 3 kilometers above the vent before drifting to the general west," it said.

"Large ballistic fragments were also observed to have been thrown around the crater within a few hundred meters and caused burning of vegetation near the volcano summit."

Stating the continued level three alert, the agency warned there were "increased chances of short-lived moderately explosive eruptions that could generate life-threatening volcanic hazards."

In August 1996, Kanlaon Volcano erupted, sending a spray of heated rocks that killed three hikers who were near the summit at the time.

The Philippines is on the seismically active region of the Pacific known as the "Ring of Fire," where more than half the world's volcanoes are located.

The most powerful volcanic explosion in the Philippines in recent years was the 1991 eruption of Pinatubo, about 100 kilometers (62 miles) from Manila, which killed more than 800 people.