About 8,000 residents were evacuated after a small active Taal volcano near Manila spewed a massive cloud of ash. Experts warned of another possibility of "hazardous explosive eruption."
Taal, one of the world's smallest active volcanoes, sits in the middle of a lake about 70km (45 miles) south of the centre of Manila. Authorities said there was a risk an eruption could cause a tsunami in the lake.
The Philippines lies on the Ring of Fire, a belt of volcanoes circling the Pacific Ocean that is also prone to earthquakes. One of the most active volcanoes in the Philippines, Taal has erupted more than 30 times in the past five centuries, most recently in 1977.
The Philippine Institute of Volcanology and Seismology also warned residents living nearby of a possible "volcanic tsunami", while flights were suspended at Manila's international airport because of the volcanic ash.