HONOLULU — A volcano on Hawaii’s Big Island erupted anew Thursday with little sound and only modest fury, spewing a steely gray plume of ash about 30,000 feet (9,100 meters) into the sky that began raining down on a nearby town.

The explosion at the summit of Kilauea came shortly after 4 a.m. following two weeks of volcanic activity that sent lava flows into neighborhoods and destroyed at least 26 homes. Scientists said the eruption was the most powerful in recent days, though it probably lasted only a few minutes.

Geologists have warned that the volcano could become even more violent, with increasing ash production and the potential that future blasts could hurl boulders the size of cows from the summit.

Toby Hazel, who lives in Pahoa, near the mountain, said she heard “a lot of booming sounds.” Those came after days of earthquakes.

“It’s just time to go — it really, really is,” she said, preparing to leave town. “I feel so sorry for the people who don’t go, because they don’t have the money, or don’t want to go to a shelter and leave their houses.”

Some people in the community closest to the volcano slept through the blast, said Kanani Aton, a spokeswoman for Hawaii County Civil Defense, who spoke to relatives and friends in the town called Volcano.

At least one person who was awake heard nothing. Epic Lava tour operator John Tarson is an early riser and only learned about the eruption after receiving an alert on his phone. The plume, a towering column of ash reaching into a hazy sky, looked different than others he’s witnessed, because of its sheer height.