Lava and broad columns of ash illuminated by lightning shot from an erupting volcano south of the Philippine capital on Monday, grounding hundreds of flights amid an alert for a possible "explosive eruption".
Homes and streets across the region surrounding the Taal volcano, which exploded to life on Sunday accompanied by a series of earthquakes, were coated in fine grit and at least 10,000 people had sought refuge in evacuation centres.
"You could not sleep anymore, because every time you closed your eyes the house would shake," restaurant owner Lia Monteverde told AFP, saying the quakes came minutes apart.
"All of us didn't sleep at all. We just prepared to leave." Taal sits in a picturesque lake and is one of the most active volcanoes in a nation where earthquakes and eruptions are a frightening and destructive part of life.
The activity is due to the Philippines' position on the Pacific "Ring of Fire", where tectonic plates collide deep below the Earth's surface.
Schools in the region around Taal, government offices and the Philippine Stock Exchange were closed as a precaution on Monday.
Aviation officials said they were working to resume flights at Manila's main international airport, which was shut down Sunday due to the risk posed to planes by the volcanic ash.
Some 240 flights have been cancelled so far, snarling plans for tens of thousands of people travelling through the Ninoy Aquino International Airport.
"I'm disappointed because this (delay) means additional expense for me and it's tiring to wait," said stranded traveler Joan Diocaras, a 28-year-old Filipino who works in Taiwan.
"But there's nothing we can do."
The eruption began with an explosion of superheated steam and rock, but by early Monday "fountains" of lava had been spotted on Taal, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.
Authorities raised the alert level to its second-highest level on Sunday, saying an "explosive eruption" could happen in "hours to days".
Phivolcs chief Renato Solidum told AFP the lava was evidence of fresh movement in the volcano, but said it was unclear if Taal would "sustain its activity".
Government seismologists recorded magma moving towards the crater of Taal, which is located 65 kilometres (40 miles) south of Manila.
Apart from the ash, some particles up to 6.4 centimetres (2.5 inches) in diameter, larger than a golf ball, had reportedly fallen in areas around the lake, Phivolcs said.
Taal's last eruption was in 1977, Solidum said.
Two years ago, Mount Mayon displaced tens of thousands of people after spewing millions of tonnes of ash, rocks and lava in the central Bicol region.
The most powerful explosion in recent years was the 1991 eruption of Mount Pinatubo, about 100 kilometres northwest of Manila, which killed more than 800 people.
It spewed an ash cloud that travelled thousands of kilometres in a matter of days and was blamed for damaging nearly two dozen aircraft.