A small volcano in a scenic lake near the Philippine capital belched a white plume of steam and ash 1.5 kilometers (1 mile) into the sky in a brief explosion on Saturday, prompting authorities to raise the alert level and urge thousands of residents to protectively evacuate from high-risk villages.
Magma came into contact with water in the main crater of Taal volcano in Batangas province, setting off the steam-driven blast that was followed by smaller emissions and accompanied by volcanic earthquakes, the Philippine Institute of Volcanology and Seismology said.
The institute raised the alarm at the 1,020-foot (311-meter) Taal, one of the world's smallest volcanoes, to the third level in a five-step warning system, meaning "there is magmatic intrusion at the main crater that may further drive succeeding eruptions."
Residents of five lakeside villages in the Batangas towns of Agoncillo and Laurel were warned of possible hazards, including fast-moving gas and molten materials and "volcanic tsunami" in the volcanic lake, and urged to evacuate to safer areas.
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Taal erupted in January 2020, displacing hundreds of thousands of people and sending clouds of ash to Manila, about 65 kilometers (40 miles) to the north, where the main airport was temporarily shut down.
Since then, the volcano has sporadically shown signs of restiveness.
The Philippines lies along the Pacific "Ring of Fire," a region prone to earthquakes and volcanic eruptions.