Hawaii issued an aviation red alert Tuesday after the Kilauea volcano spewed a plume of ash into the air, with authorities warning the volcano could become more explosive.
Rising up to 12,000 feet, ash and volcanic smog drifted southwest over 18 miles from the Kilauea crater, Reuters reports.
“We’re observing more or less continuous emission of ash now with intermittent, more energetic ash bursts or plumes,” Hawaiian Volcano Observatory (HVO) Deputy Scientist-In-Charge Steve Brantley told reporters.
“At any time, activity may become more explosive, increasing the intensity of ash production and producing ballistic projectiles near the vent,” the HVO said in a later statement.
According to the U.S. Geological Survey (USGS), a red alert means a major eruption is imminent or underway and ash could affect air traffic. It is the first time the alert has been issued since Kilauea began erupting again 12 days ago, according to Reuters.
— USGS Volcanoes🌋 (@USGSVolcanoes) May 15, 2018
The ash is a new hazard to hit Hawaii’s Big Island since the latest volcanic eruptions began. Volcanic gas and lava have destroyed 37 homes and structures and prompted the evacuation of about 2,000 residents.
On Monday, the Hawaii County Civil Defense issued a “condition red” alert for air quality around Lanipuna Gardens after a fissure opened up, releasing toxic gases. Residents were warned to stay away as the gas could cause “choking and inability to breathe.”
This story originally appeared on Time