The world's largest volcano erupted after 38 years

Mauna Loa, the world's largest active volcano, is on the Hawaiian Islands of America

This volcano was calm since 1984 but last night it erupted with anger

People wrote on social media that the flowing lava looks as if a river of fire is flowing

USGS warns Hawaiians living beneath volcano to be vigilant

Clouds of ash and smoke are visible all around, while the sky is also looking red