Manila: The Philippines has raised the alert level at its rumbling Mayon volcano to "level 3" after detecting lava flow and indications of activity that could lead to eruptions of magma.

More than 9000 people have been evacuated from villages near Mayon, a tourist attraction because of its near-perfect cone shape, following a "steam-driven eruption" on Saturday.

People within the slope of the volcano, but outside the established "danger zones", were told to take precautionary measures against possible roof collapses due to accumulated ash and rainwater, and "lahar", an Indonesian term for a volcanic mudflow.

The provincial government suspended Monday's classes from kindergarten to senior high school in some areas.