Hawaii officials activate National Guard amid Mauna Loa eruption as lava flows toward key highway

Authorities in Hawaii on Monday activated the state's NationalGuard after the eruption of Mauna Loa, the world's largest active volcano.

Gov. David Ige activated 20 Hawaii National Guard members to help with traffic control and other roles as lava from the eruption inches toward a key highway, according to the Hawaii Emergency Management Agency.

Mauna Loa, located on Hawaii's Big Island, erupted on Nov. 27 for the first time in nearly four decades as it shot 200-foot-high sprays of lava overhead.

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Authorities have assured residents that surrounding communities are far enough away from the lava flow to not be in danger for now.

Still, two shelters opened last week as a precaution and officials urged residents to be ready to evacuate if lava flows their way. Evacuations have not been ordered. The U.S. Geological Survey has also warned about drifting volcanic gases and ash that could affect air quality.

For days, lava has been steadily flowing north toward the Daniel K. Inouye Highway, the shortest route linking the east and west sides of the Big Island. Monday, lava flowed at about 20 feet per hour and was about 2.15 miles from the highway, also called Saddle Road, according to the U.S. Geological Survey.

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The lava slowed significantly after reaching flatter ground, the geological survey said.

Mauna Loa has erupted 33 times since 1843, and the last eruption was in 1984. Historically, each Mauna Loa eruption has lasted a few weeks.

Mauna Loa's eruption drew onlookers to a national park last week as the smell of volcanic gases and sulfur grew thick in the air and a large plume of gas and ash rose from the summit.

Contributing: Stephen J. Beard, Jennifer Borresen, George Petras and Ramon Padilla, USA TODAY; The Associated Press

Contact News Now Reporter Christine Fernando at cfernando@usatoday.com or follow her on Twitter at @christinetfern.

This article originally appeared on USA TODAY: Mauna Loa eruption update: Hawaii activates state National Guard