Mount Rokatenda, located in Palue Island, Sikka, East Nusa Tenggara (NTT), erupted at 11:36 p.m. local time on Saturday, spewing ash into the sky at a height of up to 4,000 meters above sea level.
The volcanic ash reportedly smothered a number of regions in Flores Island.
Palue is located to the north of Flores and can be reached in around four hours by boat from Maumere, a city in Flores.
“The volcano sent volcanic ash up to the observation post, situated around 17 kilometers of Mt. Rokatenda,” Towa Tiba Petrus, an officer at the monitoring post of Mount Iya and Mt. Rokatenda, as quoted by the Antara news agency on Sunday.
According to him, the thickness of the volcanic ash in Ropa reached one millimeter.
The volcano, Towa added, also spewed lava and produced rumbling sound heard from the monitoring post. The ash has reportedly caused respiratory diseases among children.
Towa encouraged residents to put on masks for protection from the volcanic ash. Maria Fasih, a resident of Nangapenda village in Ende, said on Sunday that she could not even see the sky.
An increase in volcanic seismic earthquake frequency was first detected in January.
A major eruption of the volcano occurred from Aug. 4 to Sept. 25, 1928, triggering a tsunami after seismic activity struck the Palue region inhabited by 266 people.