On October 25, Indonesian officials warned the country's most dangerous volcano could erupt at any time and called for tens of thousands of people to be ready for emergency evacuation.

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Indonesia alarm volcanic spray images 1
Smoke rises from Merapi volcano.

Surono - a volcanic researcher working for the Indonesian government - said the Merapi volcano showed signs of activity again in the past week, and local officials increased the warning to the highest level.

Indonesia alarm volcanic spray images 2
Smoke rises from the volcano Merapi on October 25. (Photo: Reuters)

The most recent eruption of Merapi was in 2006, when the 2,968m high mountain claimed two lives. An eruption in 1994 also killed 60 people. Earlier, a 1930 eruption also killed 1,300 people.

' Officials predict that if Merapi erupts, magma will flow over the southern slopes ', Sri Purnomo, head of Sleman district on Java island - ' home ' of Merapi volcano - says, AP quoted.

He also said they warned about 11,400 people living in the southern mountainside to prepare ' emergency evacuation '.

There are about 40,000 people living near this dangerous mountain.