It remained active for more than a year.
Moreover, the rise of Alert status was set at night when a successive earthquakes also happened, and the circulation of a lot of false information (hoax) also cause people living in safe areas to evacuate.
The Indonesian island of Bali is being evacuated with a 12km wide exclusion zone in place, scientists have said that 800 tremors have been felt from Mount Agung since Wednesday. "So I made a decision to get out to save myself with my stuff and my pet", he said, carrying a cage housing a bird.
Anticipating an eruption, the indonesian authorities are planning to divert the flights to Bali to ten other airports, including on the neighbouring island of Lombok, but also to the capital Jakarta, on the island of Java. The increase in tremors suggests an eruption is "imminent", she said.
The animals are extremely valuable to the evacuees - mostly farmers - some of whom have refused to leave the danger zone, the spokesman said.
Airlines are closely monitoring the situation, and some anticipate an eruption that would cause the release of ash clouds are risky for air traffic.
Mount Agung's eruption ni 1963 was one of the most powerful eruptions ever recorded and resulted in thousands killed.
Officials this week installed warning sirens in several townships.
Indonesia has almost 130 active volcanoes, more than any other country.
Mount Sinabung on Sumatra, an Indonesian island 2,250km from Bali, has been erupting periodically since 2010, belching a kilometres-high cloud of ash that has forced over 30,000 people to evacuate.
The entire population of Ambae is being moved from the path of the "increasingly active" Marano volcano, also known as Lombenben, according to the Pacific nation's government.