Jakarta , Indonesia ( CNN ) -- Indonesian officials have gone on high alert and have started evacuations as they warily monitor Mount Merapi , a volatile volcano in central Java that might erupt at any time . `` The local government is coordinating to evacuate around 40,000 villagers to the pre-assigned shelters , '' Neulis Auliasari of the national disaster coordination board said Monday . Seismic activity has intensified , signaling that an eruption is imminent , according to Indonesian volcanologists . The 3,000-meter Merapi is famously unpredictable , though . A pyroclastic flow -- a fast-moving burst of blistering gases and rock fragments -- is a key concern . One killed two people in 2006 and another killed more than 60 villagers in 1994 . About 1,300 people died when Merapi erupted in 1930 .
About 100 nearby residents have started evacuating . Seismic activity has increased , indicating an imminent eruption . It is famously unpredictable , though .