World's largest active volcano begins to erupt in US state of Hawaii
Still, the agency said that there are not any current indications that lava is threatening populated areas, and noted that no evacuation orders have been issued.
Authorities have issued an ashfall advisory for the Big Island and surrounding waters. The National Weather Service is urging people with respiratory illnesses to remain indoors and avoid inhaling ash particles, and urging anyone who ventures outdoors to don a mask or cover their mouth and nose with a cloth.
"Possible harm to crops and animals. Minor equipment and infrastructure damage. Reduced visibility. Widespread clean-up may be necessary," it added.
"Based on past events, the early stages of a Mauna Loa eruption can be very dynamic and the location and advance of lava flows can change rapidly," it said. "If the eruption remains in Moku‘āweoweo, lava flows will most likely be confined within the caldera walls. However, if the eruptive vents migrate outside its walls, lava flows may move rapidly downslope."