Mayon Volcano in Albay province, 360 kilometres south-east of Manila, has been in a mild state of eruption since December 14, forcing more than 47,000 people to flee their homes.
The Philippine Institute of Volcanology and Seismology warned a hazardous and explosive eruption could occur within days as an "intense level of unrest continued to persist" at the volcano famous for its near-perfect cone.
"There are more ash explosions now than in previous days and this could already be the start of a stronger explosion," said Eduardo Laguerta, resident volcanologist in Mayon.
Laguerta said lava flows have also increased and already reached 5 kilometres downslope.
"For the past 10 days, Mayon has already emitted 20 million cubic metres of lava and it appears that magma is still being replenished," he added.
Amid the warnings of a hazardous eruption, police officers and soldiers went door to door in communities at the foot of the volcano to ensure that all residents have moved out.
Provincial Governor Joey Salceda warned stubborn residents that there would be no rescue if they were trapped in the danger zones during a hazardous eruption.
"If you are there, you die there," he said. "There is no way of rescuing people if rescuers would also be killed."
Senior Superintendent William Macavinta, provincial police director, said some fathers and eldest sons have been returning to their homes during the day to check on their properties.
"If we find anyone, we will forcibly take them to evacuation centres," he said. "We will also close the danger zones so no one can come in anymore," he said.
Police officers donned Santa Claus caps and brought food to evacuation centres packed with displaced residents.
"We hope to be able to bring some cheer to the families spending Christmas away from their homes," Macavinta said.
One mother thanked the police officers for the treat.
"We can still feel the spirit of Christmas but we are sad that we will not be spending Christmas at home," the woman said. "It's really not the same."
Soldiers on the other hand held a concert for some evacuees, while the World Food Programme dispatched 20 tons of high energy biscuits to help nourish the displaced families.
The 2,472-metre volcano has erupted about 50 times since 1616. It last erupted in July 2006, forcing more than 30,000 people to flee their homes.
Mayon's most violent eruption was in 1814, when more than 1,200 people were killed and a town was buried in volcanic mud. An eruption in 1993 killed 79 people. dpa gl ms
- Deutsche Presse Agentur
- Copyright (c) dpa Deutsche Presse-Agentur GmbH