An eruption of Indonesia's Mount Anak Krakatau caused the suspension of hundreds of flights at Jakarta's main airport on Sunday after some school activities and fishing were halted.
Soekarno-Hatta International Airport posted on Instagram that it had suspended flight operations until 9:30 a.m. local time due to volcanic ash.
The suspension, extending a halt that had been scheduled until 5:30 a.m., has affected 209 flights, including several international flights, Indonesia's transportation ministry said.
Anak Krakatau has erupted since late on Friday, with volcanic ash detected at the airport early on Sunday, the ministry said in a statement.
Ash was identified as high as 20,000 feet (6,000 meters) on the Java side of the volcano and a plume of up to 50,000 feet (15,000 meters) on the Sumatra side and in some parts of Banten province in Java, the meteorological agency BMKG posted on its website.
Earthquakes, volcanic eruptions common on Pacific Ring of Fire
Anak Krakatau is roughly halfway between Java and Sumatra in Indonesia's vast island chain, which sits on the Pacific "Ring of Fire," where earthquakes and volcanic eruptions are frequent.
Indonesia's disaster mitigation agency, BNPB, "urges the public to remain calm while increasing vigilance. In the event of ashfall, people are advised to wear masks and eye protection, reduce outdoor activities, cover water sources, and exercise caution when driving, as volcanic ash can reduce visibility," said spokesperson Berton Panjaitan.
Several schools canceled activities on Saturday, with students and residents suffering eye irritation from the ash, while fishermen canceled their fishing trips due to the eruption, local media outlet Kompas reported.
The disaster mitigation agency said on Saturday there was no imminent risk of a tsunami from the volcano.
A tsunami in 2018 caused by Anak Krakatau eruptions killed hundreds and injured hundreds more on Java and Sumatra.
Anak Krakatau, which means child of Krakatau, emerged a century ago from the area once occupied by Krakatau, then known as Krakatoa. Krakatoa was destroyed in 1883, when its massive eruptions killed more than 36,000 people in a series of tsunamis.