Local authorities have warned about a “volcanic tsunami” after a small volcano erupted near the country’s capital.

According to the Philippine Institute of Volcanology and Seismology, the Taal Volcano, located about 37 miles south of Manila, spewed steam, ash, and pebbles up to 9 miles into the sky, forcing tens of thousands of people to evacuate the area.

The institute said that the danger level around Taal reached three notches, or “Alert Leve 4.” Volcanic tremors began around 11 a.m. local time and were followed by two volcanic earthquakes with a magnitude of 2.5 and 3.9, respectively.

“This means that hazardous explosive eruption is possible within hours to days,” the institute’s advisory read.

Level 5 is the highest and most hazardous explosive eruption possible, and can occur within hours to days, the advisory went on to say.

Although no immediate injuries or damage were reported, authorities scrambled to evacuate more than 6,000 people living near the volcano, and about 300,000 people are set to be moved to safety in Batangas overnight and in the next few days.

People have reported volcanic tremors, volcanic lighting and a column of steam and ash that was generated by the eruption. All departing and arriving international and domestic flights at Manila’s international airport were suspended “due to volcanic ash in the vicinity of the airport.”

The Philippines contains 452 volcanoes in which 75 percent remain the world’s most active and dormant volcanoes.