The alert for Mayon Volcano in the Philippines province of Albay has been raised from level three to level four by local authorities, meaning a "hazardous eruption is imminent".
- The volcano began suddenly erupting lava around noon local time on Monday
- All schools in the province will be suspended on January 23
- Nearby residents have been evacuated and alert area expanded to 8km
The Philippine Institute of Volcanology and Seismology said the volcano was experiencing "intense unrest".
The institute upgraded the alert to level four just a few minutes after the volcano suddenly erupted lava at around noon local time.
The highest alert level is five.
Local authorities have evacuated residents nearby and expanded the alert area to eight kilometres.
There are no reports of any chaos so far in the surrounding area.
The volcano became active on January 13 and its alert level was raised from level one to level three, before going quiet for a week.
Albay Governor Al Francis Bichara said all schools in the province would be suspended on January 23.
Mount Mayon — one of the most active volcanoes in the Philippines and famous for its beauty and near-perfect symmetry — is located on Luzon Island, more than 300 kilometres south-east of the Philippines capital Manila, and has an elevation of 2,462 metres.