Scientists are monitoring a new lava eruption of Kilauea volcano inside the Halemaumau Crater within Hawaii Volcanoes National Park.

The Hawaii island eruption started within the crater at the volcano’s summit at about 9:30 p.m. Sunday, according to the U.S. Geological Survey.

Research geophysicist Ashton Flinders of the USGS Hawaiian Volcano Observatory said three fissures opened on the walls of Halemaumau. “They started passively and effusively pouring lava into the water lake. The water lake quickly evaporated from all of the heat.”

The lava cascaded into the summit water lake, boiling off the water and forming a new lava lake at the base of the crater, officials said early this morning.

One vent has waned considerably and the remaining two vents continue to feed the the lava lake. The northern fissure was producing the tallest lava fountain at roughly 165 feet, they said.

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The Hawaii County Civil Defense Agency activated its emergency operating center upon notification of the eruption.

USGS said the lava was “completely contained” in the roughly 1,640-foot-deep crater so it did not pose a direct hazard to the public.

Just after 6 a.m. today, civil defense said the situation at the Halemaumau Crater “has stabilized.”

“The threat of ash fallout is very low but is possible in the Kau and South Kona Districts,” the agency added. By mid-morning, Civil Defense Administrator Talmadge Magno said there were reports of minor ashfall in Pahala stemming from the eruption but there was no indication of any major disruptions.

All air quality monitors show it’s in the green level which is considered satisfactory and poses minimal or no risk to the public.

“Right now, we’re good,” Magno said.

USGS officials tweeted at about 4:20 a.m. that “the fountain on the N(orth) wall of Halemaumau crater is dominant, with weaker fountaining exhibited at W(est) fissures. The lava lake is slowly rising. A billowing gas plume continues to drift to the southwest.”

Video from W rim of the caldera just before midnight. As of December 21 at 1:30 a.m. HST, the growing lava lake has almost reached the level of the lowest down-dropped block that formed during the 2018 collapse events. Over the past 2 hours, the lake has risen by ~10 m (32 ft). pic.twitter.com/Qbx1d6hbq4

— USGS Volcanoes(@USGSVolcanoes) December 21, 2020

An earthquake swarm began Sunday night accompanied by ground deformation, according to the USGS Hawaiian Volcano Observatory. Scientists detected an orange glow within the crater at the summit shortly after 9:30 p.m.

According to preliminary data, there was a 4.4-magnitude earthquake centered about 8.7 miles south of Fern Forest near the Holei Pali area of the park at a depth of 4 miles at about 10:36 p.m. The earthquake was not strong enough to generate a tsunami.

County Civil Defense officials said any ash fallout was likely in the Kau District in Wood Valley, Pahala, Naalehu and Ocean View. They initially advised the public to stay indoors to avoid exposure and to be aware of possible after shocks.

The volcano alert level was raised to a “warning” level and the aviation alert to “red” from a green “normal” level Sunday night in the wake of the eruption. The red alert means an eruption is imminent or “eruption is underway or suspect with significant emission of volcanic ash into the atmosphere.”

The aviation alert was downgraded to orange, “reflecting the less-hazardous nature of the ongoing eruption,” HVO officials said at about 10:40 a.m.

Scientists are assessing the hazards and communicating with the Hawaii County Civil Defense Agency and the national park.

The eruption currently poses limited hazards, Flinders said.

Geology teams are on rotation monitoring data feeds from tiltmeters and seismometers as well as monitoring gas concentrations.

It’s unclear at this time how long the current eruption will last, Flinders said.

Sunday’s developments mark a resumption of Kilauea lava activity since the summer of 2018 when the volcanoes 35-year eruption ended.

For the past several weeks, the observatory said scientists has recorded ground deformation and earthquake rates at the summit and upper East Rift Zone that have exceeded levels observed since the end of the 2018 eruption in Leilani Estates which destroyed more than 700 homes.

Scientists noted earthquake rates have been steadily increasing in recent months and are currently higher than they have been since the conclusion of the 2018 eruption. There were some earthquake swarms at the end of November and earlier this month, Flinders said.

Former Hawaii County mayoral candidate Ikaika Marzo, who posted video on social media of the lava as it entered Leilani Estates in the 2018 eruption and launched a community relief center dubbed Pu’uhonua O Puna, noticed an uptick of earthquakes throughout the day Sunday. “The last two hours, we’ve been having a lot of earthquakes,” Marzo said during a phone interview late Sunday night.

The USGS “Did you feel it?” service received over 500 reports within the first hours of the earthquake.

Jessica Ferracane, spokeswoman of the Hawaii Volcanoes National Park, said there were hundreds of people at the park Sunday night after information and photos of the new eruption circulated on social media. “There were definitely lines of cars waiting to get in.”

Some people did an oli or chant to welcome Pele, the goddess of fire and volcanoes.

Park officials raised concerns after they observed many people in the excitement of the new eruption who were not wearing masks or social distancing.

Hawaii Volcanoes National Park Superintendent Rhonda Loh, said, “The return of lava to the summit of Kilauea is a natural wonder, but we need the public to be fully aware that we are in the middle of the COVID-19 pandemic and to recreate responsibly, maintain social distance and to wear a mask.”

“We want to keep the park open for all to experience this new phase of volcanic activity, and we need visitors to follow safety guidelines that keep everyone safe,” Loh said in a news release.

Park officials also ask visitors to be patient as parking is limited at popular viewing points.

Ferracane noted the caldera appears 40 times bigger since the summit collapse from the 2018 eruption. Though the lava at the crater is not visible at this time, the dramatic plume billowing from the caldera and the reflection of the glowing lava is spectacular, she added.

Flinders estimated the lava lake is about 300 feet deep as of 1:45 p.m. today as lava is slowly filling up the area where the water lake used to be.

Park officials and scientists remind the public to stay safe as volcanic eruptions can be dangerous.

Eruptions can alter their behavior at any time, Ferracane said.

Flinders echoed the sentiment. “Although the situation appears stable now, things can change fairly rapidly and quickly,” Flinders said. “Don’t go anywhere you shouldn’t be.”

The park remains open 24 hours a day.

Vantage points to view the new eruption include Wahinekapu (Steaming Bluff), Kilauea Overlook, Keanakakoi, Waldron Ledge and other overlooks along Crater Rim Trail.