The United States Geological Survey released video that shows the flames spouting from cracks in the ground. Methane gas is a result of the lava burning plants and trees.
"This hot, corrosive gas mixture caused two deaths immediately adjacent to the coastal entry point in 2000, when seawater washed across recent and active lava flows", the Hawaiian Volcano Observatory said.
The gas "can seep into subsurface voids and explode when heated" or "emerge from cracks in the ground several feet away", the USGS said.
So far, more than 2,000 people have been evacuated from the area as almost two dozen fissures opened in the ground and lava slowly moved toward the sea.
At least 47 homes and other structures have been destroyed by almost two dozen fissures in the Leilani Estates and Lanipuna Gardens, and a man was seriously injured on Saturday by flying lava.
While one man almost lost his leg to flying lava splatter, no one has died yet in connection to the volcanic activity.
"Fissures near Puna Geothermal Venture are active and producing lava slowly flowing onto the property", Civil Defense said in a statement. "It's very dramatic, very eerie", geophysicist Jim Kauahikaua said.
There are four fissures bursting with lava in evacuated Leilani Estates.
Hawaiian Authorities Work to Protect Power Plant From Lava Flow
Joe Kekedi takes pictures as lava enters the ocean, generating plumes of steam near Pahoa, Hawaii. It can also cause explosions when it's ignited while trapped underground.
State and federal officials also are looking at reopening Chain of Craters Road, which is partially covered by lava rock, as an evacuation route through Hawaii Volcanoes National Park.
Janet Snyder, spokeswoman for Hawaii island Mayor Harry Kim, said the Sea Stallions can ferry up to 43 people out of the area at a time.
Hinkle and countless other residents on Hawaii's Big Island are fighting the toxic effects of sulfur dioxide, which is still spewing from cracks in the Earth's surface after the eruption on May 3.
Many homes in Puna are not built to code, or are built in zones where lava flows have already wiped out previous developments, which some residents attribute to the frontier mind-set here.
Then there's the risk of explosions at a geothermal power plant.
On Tuesday, officials finished stabilizing wells that bring up hot liquid and steam to feed a turbine generator. Stefani Hinkle said she knows her neighborhood is risky; she feels it in her burning throat.
Classified collusion briefing features top lawmakers, Federal Bureau of Investigation … and Trump's lawyer
By the time both sessions ended Thursday evening, each side had their time before reporters' microphones. But, after complaints by both parties, they added a second session for top Democrats and Republicans.