At several hundred yards long, the fissure had "lava fountaining, explosion of spatter bombs hundreds of feet into the air, and several advancing lava flow lobes moving generally northeast," according to the Hawaiian Volcano Observatory.
"Eruption of lava continues from multiple points along the northeast end of the active fissure system," the USGS said in their latest report on Sunday. "Residents in lower Puna should remain informed and heed Hawaii County Civil Defense closures, warnings, and messages."
As of late May 13th, activity was dominated by lava fountaining, explosion of spatter bombs hundreds of feet into the air, and several advancing lava flow lobes moving generally northeast from fissure 17 at the downrift (northeast) end of the new fissure system. As of about 7 pm, one lobe was 2 yards thick and advancing roughly parallel to Highway 132. The flow front was just over a half mile southeast of the intersection of Highway 132 and Noni Farms Road.
Based on overflight images late this afternoon, additional lava from fissure 17 was also moving slowly southeast. Volcanic gas emissions remain elevated.
A Civil Defense Message regarding the eruptions was released by the County of Hawaii on Monday.
"The Hawaii State Department of Health reports that the current eruption activity is producing dangerous Sulfur Dioxide (SO2) gas and other emissions that are hazardous; especially for elderly, young children and babies and people with respiratory problems," the statement read. "People who are downwind or close to the vents and lava flows are also at high risk. Be aware of the unpredictable nature of dangerous levels of SO2 gas because it can be carried far from the fissures with wind speed and direction."
The statement went on to advise civilians in the area to leave any area with volcanic activity, find shelter and monitor volcanic forecasts.
Following Sunday's report, the USGS found two additional fissures. No. 18 was described as "weakly active" while Fissure 19 is "producing a sluggish lava flow."
CNN reports that nearly 2,000 people have been evacuated since the volcanic activity began, with 37 structures destroyed along with dozens of cars and homes.