A significant amount of ash has fallen on towns near the Philippines' most active volcano after energetic eruptions of lava from the crater.
Mount Mayon in northeastern Albay province has been erupting for more than two weeks, and 84,000 people who fled the danger zone are staying in schools and other crowded shelters.
The Philippine Institute of Volcanology and Seismology said one large lava eruption lasted more than an hour and a half on Monday.
The ash plume reached 1.5 kilometres (0.9 miles) above the crater and caused significant ashfall in the towns of Camalig and Guinobatan.
Mayon has been belching red-hot lava fountains, huge columns of ash and molten rocks into the sky and plunging communities into darkness with falling ash since January 14.
It has remained at alert level four on a scale of five, indicating a more violent eruption could be imminent.
Scientists have warned that despite the repeated eruptions of lava, Mayon is still swollen with magma below the surface and could erupt explosively.
No injuries have been reported in the current eruption, but authorities have struggled to keep people out of the danger zone 8 kilometres (5 miles) from the crater. They are worried the eruption may last months, disrupting the lives and livelihoods of people in Mayon's shadow.
Provincial leaders say disaster funds are running low and have said supplies like face masks will be depleted if the eruption lasts.
The government has raised the possibility of creating a permanent "no man's land" around Mayon, a sensitive and complicated proposal that would affect tens and thousands of people living in the fertile farmlands nearby.
One possibility is expanding a national park around the base of the volcano, where trees could grow and become a buffer against volcanic flows endangering villages and towns.
Mayon has erupted about 50 times in the last 500 years, sometimes violently. In 2013, an ash eruption killed five climbers who had ventured near the summit despite warnings.
The Philippines has about 22 active volcanoes. The explosion of Mount Pinatubo in 1991 was one of the biggest volcanic eruptions of the 20th century, killing hundreds.