Aircraft are prohibited from flying below 6,000 metres in the vicinity of the volcano, and should also remain alert to the presence of volcanic ash, which can disrupt flights.

Kanlaon Volcano, one of the 24 active volcanoes in the Southeast Asian nation, has had several eruptions in the past century – the most recent of which happened in April.

The Philippine Institute of Volcanology and Seismology (Phivolcs) raised Bulusan’s alert status from 0 to 1 on its five-level scale, signalling low-level volcanic unrest and warning of possible phreatic eruptions.

The eruption sent a column of ash up to 3,500m into the sky, with thick grey-to-black clouds drifting westward and northwestward from the crater.

The 3,676-metre-high volcano, located on the boundary of Lumajang and Malang districts, is now at the second level of danger.

The eruption of the 3,676-metre-high volcano happened between 2:38 am and 9:27 am (local time), with southwesterly winds.

The volcano, situated on Halmahera Island, spewed a column of ash up to 2,000 metres into the sky. Thick white-to-grey clouds drifted south of the crater.

Mount Dukono, situated in Indonesia's eastern North Maluku province, erupted on November 26, prompting a warning for aviation, according to the country's Volcanology and Geological Disaster Mitigation Centre.

Indonesian authorities on May 16 raised the alert level for Mount Ibu, a volcano in North Maluku province, to the highest (Level 4) following a series of eruptions since last week.

Dozens of flights to and from the Indonesian tourist island of Bali were canceled as Mount Agung in the island erupted on June 28.

The Philippines warned people to keep away from Mayon volcano at least 6km in case the country’s most active volcano erupts suddenly.

Marapi volcano in West Sumatra, Indonesia erupted on June 4, spewing clouds of volcanic ash over the region of Tanah Datar in Sumatran province.

More than 1,200 people were evacuated from their homes on January 19 as Mt. Egon volcano, in the eastern Flores island of Indonesia, spewed ashes and toxic gas into the air.