Since its latest series of deadly eruptions, Java’s Mt Merapi has been spewing volcanic ash clouds into the air.

Mount Merapi launched lava and hot ash into the skies for the fourth time in eight days Wednesday morning, sending villagers and refugees scurrying to move further away from the Indonesian volcano following its most intense eruptions yet.

Indonesia's most volatile volcano erupted Tuesday after scientists warned the pressure building beneath Mount Merapi could trigger the most powerful explosion in twelve years.

When volcanoes erupt, pinpointing the regions at high risk for lethal hazards and deciding whether or not to evacuate a resistant population comprise the most difficult problems faced by hazards managers.

Indonesia, which straddles the Pacific "Ring of Fire," has about 130 active volcanoes, more than 60 of which are in densely populated areas. Weekly earthquakes rattle the nerves of everyone across this sprawling archipelago as do the tsunami warnings that follow.