Mount Marapi, one of the most active of Indonesia's 127 volcanoes located in Sumatra, erupted on 3 December 2023. Sumatra is the westernmost and third largest of Indonesia's 18,000 islands which stands at a height of 2,891 metres. The Indonesian archipelago sits on the Pacific Ring of Fire which experiences high volcanic and seismic activity due to colliding continental plates.

The volcano spewed ash as high as 3 km into the sky on 3 December covering surrounding buildings, roads and cars. The ash cloud also hampered search and rescue efforts due to low visibility. Out of the 75 hikers that were on the mountain at the time of the initial eruption, 22 casualties have been reported and many others have been evacuated and are receiving treatment in hospital for burns.

A further five eruptions were recorded on 5 December meaning search and rescue efforts have been intermittently stopped and started to protect rescuers from danger. Authorities have raised the alert to the second highest level and prohibited residents from going within 3 km of the crater.

Marapi's deadliest eruption occured in April 1979, where 60 people were killed.