"We have already raised the status of danger from normal active to alert and it looks like we may have to further raise the status by one rung soon," said Syamsurizal from the directorat of vulcanology in the West Java city of Bandung.

Tempo Interactive online said that some villagers had already left their homes on the slope of the 1,320-meter high volcano. Local officials could not be reached immediately for confirmation.

Syamsurizal said Mount Awu has begun producing small eruptions, spewing flames and thick smoke since late Tuesday.

He said that a team of geologists were travelling to Sangihe island where the mountain is located to gather more data.

Under the new alert status, the population at the foot of the mountain has been warned to remain vigilant for any signs of more vulcanic activities, he said.

The first signs of increasing vulcanic activities were reported on Sunday evening, he said.

Mount Awu last erupted in 1992 but caused no casualties while a major eruption in August 1966 killed 39 people and caused 11,000 people to flee the area surrounding the mountain.

Tempo Interactive quoted a local activist, Barlin Sumendap, as saying that there were already residents who have fled their homes on the slope of the mountain and sought shelter in the region south of the volcano.

The Indonesian archipelago sits on the so-called "Pacific Rim of Fire" noted for its volcanic and seismic activity.

TERRA.WIRE