Manila, Jan. 8 -- The Mayon Volcano hazard is increasing, but raising its alert status to Level 4 is still unlikely, at least for now, the head of the Philippine Institute of Volcanology and Seismology (Phivolcs) assured on Thursday.

Based on the Phivolcs' bulletin, 50 pyroclastic density currents (PDCs) were recorded in the past 24 hours.

"When there are many PDCs, this means there is a constant supply of magma that leads to the collapse of lava dome. This means the eruptive process is continuous, and hazard is increasing due to PDCs," Phivolcs Director Teresito Bacolcol told the Philippine News Agency in an interview.

A PDC or what they call "uson" in the Bicol Region, is like an avalanche of a mixture of ash, rock and gas. This is ...