Mauna Loa dey inside Hawaii Volcanoes National Park and e cover half of US state Big Island
Di largest active volcano for di world, Mauna Loa for Hawaii, don explode for di first time in almost 40 years.
Authorities dey mostly contain di lava flow within di summit, but residents don dey on alert about di risk, say e fit blow ashes.
US Geological Service (USGS) say di situation fit change sharp sharp and dem don raise di volcano alert level from an "advisory" to a "warning" - wey be di highest classification.
No evacuation orders dey issued and populated areas no dey like say e go dey impacted at dis stage, emergency officials tok.
Wetin be Mauna Lao
Mauna Loa wey dey located inside Hawaii Volcanoes National Park, cover half of US state Big Island.
Di volcano dey rise 13,679ft (4,169m) above sea level and reach area of more dan 2,000 sq miles (5,179 sq km).
E erupt at 23:30 local time on Sunday (09:30 GMT Monday) for Moku'āweoweo, dat na di volcano summit caldera.
Calderas na hollows or holes wey dey form under di summit at di end of an eruption.
E dey follow series of warnings say eruption dey possible afta earthquakes wey recently happun for di region, plus di more dan one dozen reported tremors on Sunday.
Authorities bin issue advisory say ash fall wey fit contaminate water supplies, kill vegetation and irritate di lungs - bin dey for di surrounding area overnight but dem don lift am.
"Based on past events, di early stages of Mauna Loa eruption fit dey very dynamic and di location and advance of lava flows fit change rapidly," na so USGS tok.
If di eruption migrate beyond di walls of di summit caldera, lava flows fit "move rapidly downslope", e add.
Mauna Loa don erupt 33 times since 1843.
According to di USGS, Mauna Loa don erupt 33 times since 1843.
Di previous eruption for 1984 bin send lava flows within 5 miles of Hilo, wey be di island most populous town.
But di Big Island population don more than double since 1980 to around 200,000 residents and Hawaii civil defence agency don warn say residents fit face a "lava disaster".
"Dis lava flows dey rarely present a risk to life, but dem fit dey extremely destructive to infrastructure," na so Dr Jessica Johnson, a British volcano geophysicist wey don work for di Hawaiian Volcano Observatory tok.
She warn say di lava flows pose risk to Hilo and Kona, anoda major population centre, come add say di volcanic gasses fit cause breathing problems for locals.
E get oda larger volcanoes but dem dey classified as dormant, meaning day dem never erupt for a long time, or extinct, meaning say dem dey almost certain say dem no go erupt in future.
Mauna Loa dey share di Big Island with Mauna Kea, eye be di tallest mountain in di world when dem measure am from di underwater base nearly 20,000ft below di ocean surface.
