INDONESIAN authorities have raised the state of alert to its highest level and increased the evacuation zone around Bali’s Mount Agung as the volcano threatens a major eruption at any moment.
Plumes of smoke and ash have been billowing up to 3,400m (11,150ft) above the mountain's summit over the weekend and the National Disaster Mitigation Agency (NDMA) has expanded the danger zone to 10 kilometres (6 miles) in places from the previous 7.5 kilometres.
The ash cloud has forced Bali’s Denpasar International Airport to close, leaving thousands of tourists stranded.
Airport spokesman Air Ahsanurrohim said 445 flights were cancelled, stranding about 59,000 travellers.
NDMA Spokesman Sutopo Purwo Nugroho told a news conference in Jakarta that the new expanded danger zone affects 22 villages, with a combined population of between 90,000 and 100,000.
He added that around 40,000 have already been evacuated but some others are refusing to leave because they don’t want to abandon their homes and livestock.
He said: “Authorities will comb the area to persuade them.
“If needed we will forcibly evacuate them.”
Residents and tourists have been warned to stay away from cold lava and rock flows, known as lahars, which have been spotted flowing down the sides of the mountain.
Mount Agung sits on Bali’s eastern coast in an area relatively untouched by tourism. While there is some tourism infrastructure, this side of the island is a world away from the heavily populated southern hub of Kuta-Seminyak-Nusa Dua.
The imminent eruption has had a massive effect on Indonesia’s top tourist destination, with official estimates putting Bali’s losses at around £83million after volcanic activity was detected in September, prompting mass evacuations.
Agung's last eruption in 1963 left more than 1,000 people dead and destroyed several villages.
Ash has settled on villages and resorts around the volcano and soldiers and police distributed masks on the weekend.
Indonesia is located on the Pacific Ring of Fire, a major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur.