Mount Anak Krakatau volcano located in the Sunda Strait in Indonesia erupted on the night of the 4th, sending volcanic ash up to 15,000 meters high into the sky. As a result, flight operations were temporarily suspended at 6 major airports including Soekarno-Hatta International Airport on the outskirts of Jakarta, and at Soekarno-Hatta Airport, 209 flights were canceled, affecting 22,000 passengers. Due to volcanic ash, air quality may be poor, so wearing masks when going outside is recommended, and if rain comes, volcanic ash is expected to be rapidly removed. Mount Anak Krakatau volcano is a volcano formed by the Krakatau volcano that was destroyed by a massive eruption in 1883 rising again.