Photos: Volcano coats Philippines with thick ash

Thick layers of ash have shut down much of Manila, as tourists and residents flee to avoid an imminent volcano eruption.

Taal volcano, one of the smallest active volcanos in the world, spewed ash for a second day on Monday, signalling a possible eruption happening soon.

"We have detected magma. It's still deep, it hasn't reached the surface. We still can expect a hazardous eruption any time," Maria Antonia Bornas, chief science research specialist at the Philippine Institute of Volcanology and Seismology, told Reuters.

Schools and businesses closed for the day in Manila. At least 30,000 people have fled the surrounding area. Two towns to the southwest of the volcano, Agoncillo and Lemery, are coated in a thick layer of ash, making the roads impassible.

Residents are being warned to wear face masks if they have to go outside, but the masks have quickly sold out around the towns.

There are fears that if a volcanic eruption were to happen, it could cause a tsunami, as the volcano is located in a lake about 70 km south of Manila.