Hawaii's Kilauea Volcano has erupted from its summit, spewing ash more than 9km into the sky.
The US Geological Survey says it erupted at 4:15am local time (2:15am Friday NZ time), and warns "at any time, activity may again become more explosive".
"Ballistic projectiles may be produced should steam-driven explosions occur," USGS says. Those projectiles could be rocks the size of cars, and could be hurled more than 1km through the air.
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The Hawaiian Volcano Observatory says the plume is expected to cover the surrounding area. Nearby residents are told to take shelter, although most have already evacuated after lava began churning from the volcano's fissures, destroying at least 26 homes and 10 other structures.
Kilauea volcano began erupting earlier this month with a number of fissures opening up. Residents of Leilani Estates and Lanipuna Gardens had to evacuate from their homes.
USGS issued a red alert on Tuesday, warning that a major eruption was imminent.