TANAH KARO, Indonesia (AP) — An Indonesian volcano shot black ash three miles into the air early Tuesday — its most powerful eruption since springing back to life after four centuries of dormancy.

The force of Mount Sinabung’s explosion could be felt five miles away.

"This one was really terrifying," said Anissa Siregar, 30, as she and her two sleepy children arrived by truck at an emergency shelter near the base, adding that the whole mountain shook violently for at least three minutes. "It just keeps getting worse."

The volcano in North Sumatra province erupted last week for the first time since 1600, catching many scientists off guard. With more than 129 active volcanoes to watch, local vulcanologists had failed to monitor it for rising magma, slight uplifts in land and other signs of seismic activity.

There are fears that current activity could foreshadow a much more destructive explosion in the next few weeks or months, though it is possible, too, that the mountain will go back to sleep after letting off steam.

More than 30,000 people living along the volcano’s fertile slopes have been relocated to cramped refugee camps, mosques and churches in nearby villages.

But some — like Siregar, the mother who fled with her children — have insisted on returning to the danger zone to check on their homes and their dust covered crops.

The government sent trucks to the mountain before Tuesday’s eruption to help carry them back to safety.

Surono, who heads the nation’s volcano alert center, said intensity at the mountain is clearly increasing.

There were more than 80 volcanic earthquakes in the 24-hour lead up to the blast, compared to 50 on Friday, when ash and debris shot nearly two miles (3,000 meters) into the air.

The eruption early Tuesday occurred just after midnight during a torrential downpour. Witnesses said volcanic ash and mud oozed down the mountain’s slopes, flooding into abandoned homes.

Indonesia is a seismically charged region because of its location on the so-called "Ring of Fire" — a series of fault lines stretching from the Western Hemisphere through Japan and Southeast Asia.

It has recorded some of the largest eruptions in history.

The 1815 explosion of Mount Tambora buried the inhabitants of Sumbawa Island under searing ash, gas and rock, killing an estimated 88,000 people.

The 1883 eruption of Krakatoa could be heard 2,000 miles (3,200 kilometers) away and blackened skies region-wide for months. At least 36,000 people were killed in the blast and the tsunami that followed.

Associated Press Writer Niniek Karmini contributed to this report from Jakarta.