Lava crept through residential areas on Hawaii’s Big Island, destroying dozens more structures, including four homes, over the past 24 hours as Kilauea capped off another week of volcanic activity.

Fissures near the Lanipuna Gardens neighborhood in the town of Pahoa continued to erupt, sending slow-moving lava along residential roads. Four homes were destroyed Saturday morning, after lava advanced by 1,000 feet in less than an hour, the Hawaii County Civil Defense Center said. A short explosion from Kilauea sent an ash cloud about 10,000 feet into the air around midnight.

On Friday, several fissures, including one that just formed, spewed fresh lava from Kilauea’s summit, destroying 40 structures in the morning, the center said. By afternoon, fast-moving lava had isolated 40 homes in the area. Four people were airlifted by county and National Guard helicopters.

“With fresher, hotter magma, there’s the potential that the lava flows can move with greater ease and therefore cover more area,” Janet Babb, a geologist for the U.S. Geological Survey, told Hawaii News Now.

Resident Ikaika Marzo likened the sound of lava to as many as 20 jets taking off at once in people’s back yards.

“It’s huge grenades going off,” he told Hawaii News Now. “It shakes the whole community.”

Lava erupts on the outskirts of Pahoa, Hawaii, during ongoing eruptions of the Kilauea volcano. (Terray Sylvester/Reuters)

Edwin Montoya said a fissure that sent lava across the road began as a “little crack in the ground, with a little lava coming out.”

“Now it’s a big crater that opened up where the small little crack in the ground was,” he told the Associated Press.

Montoya, who lives with his daughter on a farm, said he managed to take some valuables from his property Saturday morning, including batteries and $4,000 worth of equipment and solar panels.

Mandatory evacuations have remained in place in Lanipuna Gardens and the neighboring Leilani Estates, while other residents have been urged to evacuate should continued volcanic activity threaten Highway 137, which runs along the Big Island’s southeastern coastline.

For nearly three weeks, Kilauea, one of the world’s most active volcanoes, has been spewing bright red-orange lava and sending thousands of residents fleeing from their homes. Before dawn Thursday, a big explosion sent a plume of ash about 30,000 feet into the sky.

On Tuesday, the volcano’s Halemaumau Crater produced a towering ash plume that reached 12,000 feet at its peak and could be seen for miles. People climbed up trees at the nearby Volcano Golf and Country Club to take pictures of the imposing dark plume that billowed over the greens. Others simply continued golfing as an apocalyptic cloud mushroomed behind them, The Washington Post’s Amy B Wang wrote.

Scientists predict that if the lava lake at the top of Kilauea continues to drop and eventually meets groundwater, there would be an enormous steam explosion that could send 10-ton molten rocks — or “boulders the size of cows” — as far as a half-mile from the crater. Those within 20 miles of the crater could also be subject to smaller rocks and ash.

In the meantime, scientists say they have no way of knowing if the volcanic activity is just in its early stages or nearing its end.

“We’re kind of all right now in this world of uncertainty,” Tom Shea, a volcanologist at the University of Hawaii, told the AP.

Amy B Wang contributed to this article.

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