MANILA, Philippines - Authorities moved thousands of villagers from harm's way near the Philippines' most active volcano yesterday after it oozed lava and shot plumes of ash. They said evacuees probably would spend a bleak Christmas in an evacuation center.

State volcanologists raised the alert level on the cone-shaped, 8,070-foot Mayon volcano overnight to two steps below eruption after ash explosions and dark-orange lava fragments glowing in the dark trickled down the mountain slope.

Nearly 50,000 people live in a five-mile radius around the mountain, and authorities began moving thousands in case it erupts, Albay Gov. Joey Salceda said.

The first of 20 vehicles, including army trucks, were sent to villages to take residents to schools and other temporary housing, provincial emergency management official Jukes Nunez said.

"It's 10 days before Christmas," Nunez said. "Most likely people will be in evacuation centers, and if Mayon's activity won't ease down, we will not allow them to return to their homes. It's difficult and sad, especially for children."

Magma had been rising at the volcano over the last two weeks and began to ooze out of its crater last night, but it could get worse in the coming days, said Renato Solidum, head of the Philippine Institute of Volcanology and Seismology.

"Now lava is trickling down, but if the ascent of magma is sustained, there will be laval flows," Solidum said. "There is also the possibility of an explosion."

Residents in the central province of Albay are used to moving away from Mayon, which spewed ash last month and prompted the evacuation of some villages. About 30,000 people were moved when it last erupted in 2006. Typhoon-triggered mudslides near the mountain later that year buried entire villages, killing more than 1,000 people.

Mayon's most violent eruption, in 1814, killed more than 1,200 people and buried a town in mud. A 1993 eruption killed 79 people.

The Philippines lies along the Pacific "Ring of Fire," where volcanic activity and earthquakes are common. About 22 out of 37 volcanoes in the archipelago are active.