More than 75,600 people have been evacuated in Bali, after dramatic increases in seismic activity sparked fears Mount Agung could erupt in a “matter of hours”.
The Indonesian Center for Volcanology and Geological Hazard Mitigation (CVGHM) has raised the volcano alert to 4, meaning an eruption can be expected at any time.
Balinese locals continue to flee the danger zone, which stretches 7.5 miles around the volcano.
More than 1,000 tremors were recorded on Mount Agung on Monday and Tuesday, including a magnitude 4.2 quake at 11am BST today.
After the quake, the European-Mediterranean Seismological Centre tweeted: “Strongest quake so far while the volcano may be about to erupt.
“Agung volcano is said to be close to erupting and the Bali island just shaken by a M4.2 earthquake.”
The map below shows the quake struck the island of Bali at a depth of 5km.
Meanwhile, shocking graphs show sharp rises in seismic activity around Mount Agung over the past few weeks.
And more frequent shallow earthquakes could be a sign that a new batch of magma has moved just under the summit, according to Volcano Discovery.
Devy Kamil Syahbana, a seismologist from Indonesia’s volcanology centre, told the Guardian that such high seismic energy has never been recorded from Mount Agung.
He said: “We need to pay attention because these kinds of earthquakes indicate the movement of magma and increase the probability of an eruption.”
Tens of thousands of people have left the danger zone, but officials are still working to evacuate some who refuse to leave their homes.
Speaking at a press conference, a disaster mitigation agency spokesman said: “There are still people who don’t want to be evacuated.
“The reason is firstly, the mountain hasn’t erupted yet. Secondly, they are worried about their livestock.”
The latest Foreign Office advice to Britons planning to visit the region says that Indonesia’s volcanic alert level indicates “an eruption is possible in the next 24 hours”.
The Foreign Office says: “You should follow the advice of the local authorities and stay outside the exclusion zone. If there is an eruption, volcanic ash clouds could cause flight disruptions.
“In the event of volcanic ash clouds you should confirm your travel arrangements directly with your airline or travel agent before travelling to the airport.”
Mount Agung, which is the largest volcano in Bali, has not erupted since 1963, when two major eruptions killed some 1,700 people.
The volcano is part of the so-called Ring of Fire, a circle of volcanoes that surrounds Indonesia.