MANILA: Thousands of people were ordered to evacuate from their homes near a Philippine volcano Saturday after an eruption sent ash and steam hundreds of metres into the sky.
Taal volcano, which sits in a lake south of Manila, exploded with a "short-lived" burst at 7:22 am (2322 GMT), the Philippine Institute of Volcanology and Seismology said in a statement.
It warned further eruptions were possible, which it said could trigger dangerous, fast-moving volcanic flows of gas, ash and debris, as well as a tsunami.
The seismological agency "strongly" recommended residents living in vulnerable communities around the lake be evacuated, as it raised the alert level from two to three.
The initial eruption was followed by "nearly continuous phreatomagmatic activity" that sent plumes stretching 1,500 metres (4,900 feet) into the air.
A phreatomagmatic eruption happens when molten rock comes into contact with underground or surface water, said Princess Cosalan, a scientist at the agency, likening it to pouring "water on a hot pan".
Cosalan told AFP that ash and steam emissions had quietened in the hours after the initial burst, but said the institute's on-site sensors continued to detect volcanic earthquakes and another eruption was "possible".
"There is magmatic intrusion at the Main Crater that may further drive succeeding eruptions," the agency warned.
Residents of five villages were ordered to leave their homes, regional civil defence spokesman Kelvin John Reyes told AFP.
More than 12,000 people live in the settlements, according to the latest available official data.
Police have been deployed to stop people entering the high-risk areas.
One of the most active volcanoes
Taal is one of the most active volcanoes in a nation hit periodically by eruptions and earthquakes due to its location on the Pacific "Ring of Fire" - a zone of intense seismic activity.
Access to the volcano island, which was once home to a community of thousands, has been prohibited since January 2020.
That was when an eruption shot ash 15 kilometres (nine miles) high and spewed red-hot lava, crushing scores of homes, killing livestock and sending tens of thousands into shelters.
Last July, the seismological agency raised the alert level to three after Taal burst to life again.
It belched sulphur dioxide for several days, creating a thick haze over the capital and surrounding provinces.
The alert level was lowered back to two before Saturday's eruption.