Phivolcs’ 9 a.m. bulletin yesterday said the main lava flow which cascaded from the Mabinit Channel on the northeast section of the volcano has "advanced some 70 meters in 24 hours."

"It is now almost at the six-km-PDZ boundary, 5.9 kms from the crater," Phivolcs said.

In a phone interview, Phivolcs Director Dr. Renato Solidum said the PDZ in the southeastern part of the volcano or the Bonga Gully had been extended up to eight kms. The Mayon’s crater is lowest at the Bonga Gully.

"The (residents in the) southeast should be always on alert... Sila ang unang ie-evacuate (if the volcanic activity persists)," he said.

He said the public is warned "not to get close to the lava flow" since volcanic hazards such as pyroclastic avalanches pose a significant threat.

The sulfur dioxide emission rate remained high yesterday at 7,050 tons per day (t/d) while 450 tremor episodes and 16 volcanic earthquakes had been recorded.

Phivolcs said the tremor episodes were caused by the continuous tumbling of lava blocks into gullies in the southern portion of the summit while the volcanic earthquakes were generated by the ongoing intrusion and ascent of magma towards the crater.

"Fine ash and gases are also being produced by large lava blocks breaking on impact," Phivolcs said.

Mayon volcano’s alert status remains at level 3 (increased tendency towards eruption), which means that the volcano is currently at a "relatively high level of unrest." It could also mean that the "magma is close to the crater."

Last Tuesday, Phivolcs advised residents and tourists to "keep a safe distance" from the Mayon volcano as the lava flow, particularly in Legazpi City’s Mabinit Channel, has further advanced to approximately 5.8 aerial kms or just 200 meters away from the boundary of the six-km PDZ.