As of today, at least 10 such fissures were reported in the neighbourhood, including two that had opened anew. More outbreaks are likely along the rift zone, officials said.
Drone footage showed lava spouting along the fissures that had formed, creeping towards Leilani Estates homes and leaving lines of smoldering trees in their wake. The flows destroyed or cut off several streets in the neighbourhood - typically home to about 1700 people, before most of them evacuated last week.
At least five homes in the subdivision have been destroyed by fire, according to Hawaii County Mayor Harry Kim, who warned residents to heed evacuation notices. On Saturday, Kim had said there might be a small window of time residents could return home to rescue pets or important items left behind, but said it remained too dangerous yesterday, Hawaii News Now reported.
"This is a very fast-moving situation," Kim told the news site. "This is unfortunately not the end."
Several earthquakes, including the strongest to hit Hawaii in more than four decades, have jolted the island's residents, some as they were in the midst of evacuating.
And noxious fumes from the volcano could be the greatest threat to public health after the eruption.
The island has been regularly shaken by earthquakes since last week. A 5.6-magnitude quake hit south of the volcano, followed about an hour later by a 6.9-magnitude temblor, according to the US Geological Survey.
The latter was felt as far away as Oahu and struck in nearly the exact same place as a deadly 7.4-magnitude earthquake in 1975, according to the Geological Survey.
Videos posted to social media showed homes visibly shaking, items clattering to the floor at supermarkets and waves forming in swimming pools as the 6.9-magnitude quake rattled the Big Island.
"I think the whole island felt it," said Cori Chong, who was in her bedroom with her dog, Monty, when the quake struck, frightening both of them. Even though Chong lives on the Hamakua coast, about an hour north of the earthquake's epicentre, the shaking in her home was so violent that it caused furniture to move and glass to shatter.
David Burlingame, who lives about 3.2km west of Leilani Estates, said he and a friend ran outside when the earthquake hit "and watched my house just shake back and forth".
"Everybody is kind of on edge," Burlingame said of both the potential for additional earthquakes and the unpredictability of the lava flows. "The worst part is kind of waiting to see, because you really never can tell what can happen."
The earthquakes also prompted the rare closure of Hawaii Volcanoes National Park, after they damaged some of the park's trails, craters and roads.
The first earthquake triggered a cliff to collapse into the ocean, and fissures began to appear in the ground at a popular overlook near the Jaggar Museum.
Park officials said they cancelled hikes and evacuated about 2600 visitors, along with all nonemergency employees.
"Safety is our main priority at Hawaii Volcanoes National Park, and it is not safe to be here," park superintendent Cindy Orlando said. "We will monitor the situation closely, and reopen when it is safe to do so."
The county civil defence agency reported that the threat of a tsunami was low after the earthquakes, though officials warned that residents were not in the clear yet.
"Everything is still elevated," said agency administrator Talmadge Magno, according to Hawaii News Now. "It kind of gets you nervous."
The eruption prompted the County of Hawaii's acting Mayor, Wil Okabe, to declare a state of emergency. Governor David Ige also issued an emergency proclamation and activated Hawaii's National Guard to help with evacuations.
Jordan Sonner, a Big Island real estate agent, was on another part of the island taking pictures for an upcoming listing when she "got the call that there was lava in Leilani" and rushed home, just outside Leilani Estates.
"To describe it in a single word: chaos," Sonner said, of the evacuation. "My immediate threat was not the lava. It was the sulphur dioxide gas."
It took Sonner about an hour and a half to reach her home, grab important documents and her pets - four dogs and a chinchilla - and scramble back out, she said. She's now staying with a friend in Mountain View, about 32km northwest of Leilani Estates, and expects it could be a long while before it's safe for residents to return.
"It's so hard to tell what is going to happen because it's so early. This volcano being a shield volcano, the way that it erupts, it just erupts slowly," Sonner said. "We kind of just have to sit and wait to see what direction the lava is going to flow in and what other fissures are going to open up. This is far from over."
When asked whether she was afraid she would lose her home, Sonner paused, before describing the uniqueness of the community there.
"The way I kind of look at it is, the land doesn't really belong to us. It belongs to Pele," Sonner said, referring to the Hawaiian volcano goddess. "We get to live on it while we can and if she wants it back, she'll take it. I have good insurance."
At least a few hundred people had evacuated their homes in Leilani Estates and nearby Lanipuna Gardens, taking refuge at churches, Red Cross shelters and with family and friends in other parts of Hawaii, representative Tulsi Gabbard told CNN's Jake Tapper.
Gabbard warned that the threat from the sulphur dioxide could be more dangerous than the lava flows, which had stopped in places after the eruption. If conditions worsened, even first responders would not be able to go into the affected neighborhoods to help trapped residents, she added.
"Sulphur dioxide gas can be so toxic and thick in some areas that it can be fatal, especially to those who have respiratory illnesses," Gabbard said. "The wind can push [the gas] in different directions, so that's a very serious concern given the high levels and, you know, people don't necessarily have the kinds of protective gas masks that they would need if they were right in the thick of this gas."
Kilauea is the youngest and most active volcano on Hawaii Island, according to USGS. It is made of basalt, a fluid lava that makes for effusive - rather than explosive - eruptions.
Rather than building up into a steep, towering peak like Krakatoa in Indonesia or Mt St Helens in Washington state, the fluid rock at Kilauea creates a broad, shallow dome known as a shield volcano.
Shield volcanoes "are really voluminous, the largest volcanoes on Earth, but because they have those long, low-angle slopes, they're not very dramatic", said Tari Mattox, a geologist who worked at the Hawaii Volcano Observatory for six years. "People are surprised when they go to Hawaii and they say, "Where's the volcano?"And I tell them, "You're standing on it!'"
Rocks moving upward through the mantle beneath Hawaii begin to melt about 80km beneath the surface. That magma is less dense than the surrounding rock, so it continues to rise until it "ponds" in a reservoir roughly 4.8km wide and 1.5 to 6.5km beneath the summit. As pressure builds in the magma chamber, the magma seeks weak spots in the surrounding rock, squeezing through until it reaches a vent to the surface.
Geologists said the seismic activities around Puna most closely resemble the events that precipitated a 1955 eruption, according to Hawaii News Now. That eruption lasted about three months and left almost 1618ha of land covered in lava, the news site reported.
More recently in 2014, lava again threatened the Puna district, specifically the town of Pahoa and its surrounding area, the Post reported. During that eruption, lava flowed as quickly as 20m per hour, and up to 60 structures were at risk.
