Mount Semeru is a dangerously active volcano in South Sulawesi, Indonesia. It first erupted in 1974. In 2000, a major earthquake and subsequent tsunami killed 13,000 people. It is one of Indonesia’s top tourist attractions, attracting one million visitors a year, including nearly 18,000 tourists last month.
On Saturday, Sept 22, an explosion occurred at the volcano.
It led to a rapidly rising ash cloud, meaning that flights were suspended on Monday and could not land in the following days. Surabaya airport, located on the island of East Java, was closed on Monday.
From Sunday, Sept 24, flights have returned to normal. Authorities told those at risk of an evacuation to stay indoors.
Authorities are still working on assessment plans of the ash cloud and areas that need to be evacuated.
Authorities estimate the ash cloud reached heights of up to 1,800m (5,040ft).
Eyewitnesses say the volcano came alive on Saturday morning with ash and gas raining down in a ball of fire.
Massive plumes of red-hot ash destroyed homes and fields, causing nearby residents to flee the area.