The Taal volcano emitted 12,000 tonnes of toxic gas sulfur dioxide while residents were stuck at home due to the Covid-19 lockdown in the Philippines.
Footage shows thick smoke blanketing the horizon around the volcano as it spews out gas in Batangas province on August 20.
The Philippine Institute of Volcanology and Seismology (PHIVOLCS) also warned residents in the area after volcanic smog or vog was detected continuously coming out of Taal.
Millions in the nearby capital Manila are stuck at home due to a Covid-19 lockdown.
In a statement, the agency said: ‘Because of unprecedented high SO2 degassing from Taal Main Crater, local government units are additionally advised to conduct health checks on communities affected by vog.
‘Civil aviation authorities must advise pilots to avoid flying over Taal Volcano Island as airborne ash and ballistic fragments from sudden explosions and pyroclastic density currents such as base surges may pose hazards to aircraft.’
Vog is a form of air pollution that results when sulfur dioxide and other gases and particles emitted by an erupting volcano react with oxygen and moisture in the presence of sunlight.