Photo taken in Lumajang on Jan. 17, 2021 shows volcanic materials spewing from Mount Semeru, an active volcano in East Java, Indonesia. (Photo by Aditya Hendra/Xinhua)

Photo taken on Jan. 17, 2021 shows flowers covered by volcanic ash from Mount Semeru, an active volcano in East Java, Indonesia. (Photo by Aditya Hendra/Xinhua)

Photo taken on Jan. 17, 2021 shows police officers patrolling near a mosque covered by volcanic ash from Mount Semeru, an active volcano in East Java, Indonesia. (Photo by Aditya Hendra/Xinhua)

Photo taken in Lumajang on Jan. 17, 2021 shows volcanic materials spewing from Mount Semeru, an active volcano in East Java, Indonesia. (Photo by Aditya Hendra/Xinhua)