The last time Hawaii's Mauna Loa erupted was in 1984.
Hawaii’s Mauna Loa, the world’s largest active volcano, has erupted for the first time in nearly 40 years, according to reports.
Mauna Loa began erupting Sunday, the U.S. Geological Survey said. The lava wasn't expected to threaten populated areas, officials said, but they advised all residents on Hawaii Island who are "at risk from Mauna Loa lava flows" to "review preparedness and refer to Hawai'i County Civil Defense information for further guidance."
"Lava flows are not threatening any downslope communities and all indications are that the eruption will remain in the Northeast Rift Zone," the USGS said in a statement.
The early stages of an eruption from that particular volcano can be dynamic, the agency warned, adding that "lava flows can change rapidly” the USGS said, basing its assessment on previous records from when it has erupted in the past.
The Hawaiian Volcano Observatory said it was "in close consultation with emergency management partners and will be monitoring the volcano closely to provide further updates on activity."
Locals have also been warned that volcanic gas, ash and thin glass fibers could be carried downwind, CBS News reported.
Mauna Loa has erupted 33 times since 1843, according to the USGS. It last erupted in 1984, when lava spilled down its slopes and came within 4.5 miles of the island's biggest town, Hilo, CBS News reported.