Mount Sinabung Erupts

Mount Sinabung spews volcanic materials into the sky in Karo, North Sumatra, Indonesia, Monday, Aug. 30, 2010. The volcano that had been dormant for more than four centuries erupted for the second day in a row, sending clouds of ash a mile into the air and forcing the evacuation of more than 30,000 people.

Sinabung last erupted in 1600, so observers don't know its eruption pattern and admitted over the weekend they had not monitored it closely before it started rumbling days ago in the lead-up to Sunday's first, less-powerful blast.

Northern Sumatra is part of Indonesia, which consists of 17,500 islands and is prone to volcanic eruptions and earthquakes because of its location within the so-called "Ring of Fire" — a series of fault lines stretching from the Western Hemisphere through Japan and Southeast Asia.

Villagers ride a motorbike as Mount Sinabung spews volcanic smoke in the background in Karo, North Sumatra, Indonesia, Sunday, Aug. 29, 2010. The volcano spewed hot lava and sand high into the sky early Sunday in its first eruption in 400 years causing thousands of people living around its slope to evacuate their homes

Residents ride on top of a van as they evacuate villages after Mount Sinabung erupted Sunday.

Another view of Mount Sinabung.

Villagers who live on the slope of Mount Sinabung carry their belongings at a temporary shelter in Karo, North Sumatra, Indonesia, Sunday, Aug. 29, 2010.

Villagers who live on the slope of Mount Sinabung receive food at a temporary shelter in Karo, North Sumatra, Indonesia, Sunday, Aug. 29, 2010. The volcano spewed hot lava and sand high into the sky early Sunday in its first eruption in 400 years causing thousands of people living around its slope to evacuate their homes.

A villager rides a buffalo cart with a backdrop of Mount Sinabung, in Karo, North Sumatra, Indonesia, Sunday, Aug. 29, 2010.

A villager loads his goats into a van as he evacuates his village to flee from erupting Mount Sinabung in Karo, North Sumatra, Indonesia, Sunday, Aug. 29, 2010.

A villager wears a mask to protect himself from the volcanic ash from erupting Mount Sinabung in Karo, North Sumatra, Indonesia, Sunday, Aug. 29, 2010

Villagers who flee erupting Mount Sinabung rest at a temporary shelter in Karo, North Sumatra, Indonesia, Sunday, Aug. 29, 2010.

Residents ride a motorbike as they evacuate their village to flee from erupting Mount Sinabung in Karo, North Sumatra, Indonesia, Sunday, Aug. 29, 2010.

A man and his son look on as the Sinabung volcano spews thick smoke on Sunday, August 29, 2010.

Villagers watch as Mount Sinabung spews volcanic materials in Karo, North Sumatra, Indonesia, Monday, Aug. 30, 2010.

Mount Sinabung spews volcanic materials in Karo, North Sumatra, Indonesia, Monday, Aug. 30, 2010.

Mount Sinabung spews volcanic materials into the sky in Karo, North Sumatra, Indonesia, Monday, Aug. 30, 2010. Homes and croplands were blanketed in gray soot, and the air was thick with the smell of sulfur.

Mount Sinabung spews volcanic materials into the sky in Karo, North Sumatra, Indonesia, Monday, Aug. 30, 2010.

Villagers flee their homes as Mount Sinabung spews volcanic materials in Karo, North Sumatra, Indonesia, Monday, Aug. 30, 2010.

A time exposure of the summit of Mount Sinabung as it erupts on August 31, 2010.

Evacuees are seen as Mount Sinabung spews volcanic material in Tanah Karo, North Sumatra, Indonesia, Tuesday, Aug 31, 2010.

Indonesian children who fled their homes near the erupting Mount Sinabung play at a temporary shelter in Brastagi, North Sumatra, Indonesia, Tuesday, Aug. 31, 2010.

An Indonesian medical at a temporary shelter in Brastagi, North Sumatra, talks to a villager who fled the erupting Mount Sinabung, Tuesday, Aug. 31, 2010.

A resident from a village near the erupting Mount Sinabung rests at a temporary shelter in Karo district in North Sumatra, August 31, 2010.

The eruption of the long-dormant volcano has put the region on the highest alert level.

A man carries firewood as Mount Sinabung spews volcanic material in Tanah Karo, North Sumatra, Indonesia, Tuesday, Aug 31, 2010. Villagers briefly returned to their homes Tuesday to check their farms along the volcano's fertile slopes. Many fields were covered in gray soot.

With rumbling Mount Sinabung in the background, an Indonesian youth drags a goat as he briefly returns to his village to check on his livestock, in Tanah Karo, North Sumatra, Indonesia, Tuesday, Aug. 31, 2010.

Mount Sinabung spews clouds of hot ash and smoke for the third day of its recent activity, Tuesday, Aug. 31, 2010.

Mount Sinabung, which has been dormant for more than four centuries, has the potential to be very destructive. Magma forming inside the conical tip can act as a plug, allowing pressure to build up until it reaches a bursting point.

Mount Sinabung spews volcanic materials on Friday, Sept. 3, 2010. The force of the eruption — the strongest so far — could be felt five miles away.

A time exposure taken at 12:31 a.m. on September 7, 2010 shows a giant plume of volcanic ash rising from the crater of Mount Sinabung during its latest eruption - its biggest yet - as seen from Tanah Karo district in North Sumatra province. Some witnesses reported seeing an orange glow (presumably magma) in cracks along the volcano's slopes for the first time.

The volcano shot volcanic ash high into the air Tuesday, dusting villages 15 miles away in its most powerful eruption since awakening last week.

Villagers ride their motorcycles on a road covered with ash in Tanah Karo, North Sumatra, Indonesia, Tuesday, Sept. 7, 2010.