Indonesia has raised its warning for Bali's Mount Agung volcano to the top level four alert, closed the holiday island's airport and told residents around the mountain to immediately evacuate, warning of an "imminent" risk of a larger eruption.

Mount Agung volcano eruption Bali Indonesia
Mount Agung volcano erupting as seen from Culik village in Karangasem, Bali, Indonesia Johannes P Christo/Reuters

The alert level on Agung had been raised to the maximum in September, but was lowered in October when seismic activity calmed. However, volcanologists now say the volcano has entered a new phase with magma now visible at Agung's peak, meaning a greater risk of a larger eruption.

"Plumes of smoke are occasionally accompanied by explosive eruptions and the sound of weak blasts that can be heard up to 12 km (7 miles) from the peak," the Disaster Mitigation Agency (BNPB) said. A spokesman for BNBP said the lava "will certainly spill over to the slopes". Volcanologists say the lava's presence is sometimes reflected in the ash plume which takes on a reddish-orange glow even in daytime.

Agency spokesman Sutopo Purwo Nugroho said bigger eruptions than those currently happening are possible based on the information the disaster agency is receiving from the volcano monitoring centre.

Cold lava flows, known as lahar, have been witnessed at a number of locations on the mountainside. Lahar carrying mud and large boulders can destroy houses, bridges and roads in its path.

Residents have been warned to "immediately evacuate" a danger zone around Agung in a radius of 8-10 km (5-6 miles). Sutopo, a BNPB spokesman, said there had been no casualties so far and 40,000 people had left the area, but tens of thousands still needed to move and warned authorities would move them by force if necessary.

Bali's I Gusti Ngurah Rai airport, which is about 60 km (40 miles) from the volcano, will be closed for 24 hours. The closure of the airport is having a disruptive effect on flights around Indonesia and the region. Bali is a hub airport in Indonesia with many flights transiting there for domestic as well as international destinations. Planes that would have flown other routes Monday are now stuck on the tarmac in Bali.

Authorities say the airport closure is in effect until Tuesday morning and is being reviewed every six hours.

Stranded tourists could leave Bali by taking a ferry to neighbouring Java and then travel by land to the nearest airports. Major ferry crossing points have been advised to prepare for a surge in passengers and vehicles.

Map showing location of Mount Agung onBali,Indonesia
Map showing location of Mount Agung onBali,Indonesia Google

The past 24 hours have been crazy, and when I posted yesterday I never expected it to go so viral. A huge thanks to everyone who has commented, shared, etc for helping this post be seen by over half a million people. I’m trying my best to respond to each and every comment and it really does mean the world that you’ve all been reaching out. There’s been a lot of press, and I’m trying to turn that into a positive impact because the families displaced by this eruption need all the help they can get. So find a non-profit that you believe in and show them some support. Imagine the impact we could have if everyone who liked my last photo donated even the cost of their morning coffee to support the amazing work of @balistreetkidsproject, @missionpawsible or any other groups working hard in the area. . . . . . . . #wanderlust #exploreeverything #volcano #bravogreatphoto #lifeofadventure #theadventureproject #peoplescreatives #mountagung #folktravel #picoftheday #welltraveled #agung #whatchthisinstagood #beautifuldestinations #bali #livefolkindonesia #livefolk #passionpassport #mytinyatlas #letsgosomewhere #wanderlust #instagood #igmasters #thewellcollective #verilymoment #mountagung #traveltagged #travelphotography

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The power of Mother Nature 🌋. . Mount Agung volcano on island of Bali erupted for a second time in less than a week on Saturday evening, sending a grey-black plume of ash and steam at least 1,500 meters into the sky. . "Tourism in Bali is still safe, except in the danger zone around Mount Agung," Indonesia's Disaster Mitigation Agency said in a statement, referring to an area that extends to a radius of up to 7.5 km from the summit. . "There has not been an increase in seismic and volcanic activity after the (Tuesday) eruption and until this afternoon," said the statement, noting that it had not changed its emergency status for Agung from level 3. . However we want to let you know, for all tourists out there which are the main tourists destinations is about 75 km from “red zone” area. It’s still safe places to go so don't worry . . . Photo by @goedebawa ▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂ . Inquiries: .

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