A veil of smog obscured Taal Volcano in the Philippines.

Video shows the haze surrounding the volcano in Batangas province on September 6.

Resident Reynante De Villa said: 'There was thick smog today, and the area smelled like sulfur and rotten egg.'

State seismological agency PHIVOLCS said the Taal Volcano was on Alert Level 1, indicating 'low-level unrest' with possible steam-driven eruptions, volcanic earthquakes, and volcanic gas build-up.

In a September 6 bulletin, the agency said there were four volcanic earthquakes recorded over a 24-hour period.

The Philippines is an archipelago of more than 7,000 islands inside the Pacific 'Ring of Fire' where the majority of Earth's volcano eruptions and earthquakes happen.