Indonesian scientists on Tuesday upgraded an alert status for Mount Merapi volcano on densely populated Java island after almost 100 tremors were recorded at the weekend.
The volcano, which looms above plains north of Yogyakarta city, Central Java province, emitted at least 95 tremors since Friday, forcing authorities to raise Merapi's status to the "beware" alert level, up a notch from normal.
The tremors caused panic among residents of Jrakah village on the northern slope of the volcano, said a local official who identified himself as Panut.
"Officials have been sent to brief them about the status of the volcano. So far, no smoke has come out of the crater," he told AFP from a monitoring post near the crater.
He said officials had told residents to remain cautious and practice evacuation procedures.
Mount Merapi is a 2,911 meter (9,606 foot) high volcano that has been rumbling intermittently during the past four years.
Indonesia sits on the "Pacific Rim of Fire" noted for its volcanic and seismic activity. The country has more than 100 active volcanoes.
