(STUMPY POINT) -- A wildfire at the Alligator River National Wildlife Refuge at inland Dare and Hyde Counties prompted a  smoke advisory for Beaufort, Hyde, Craven, Dare, Jones, Onslow, Pamlico and Carteret counties.

As of Monday morning the fire had scorched 21,000 acres. U.S. Highway 264 between Stumpy Point and Hyde County was closed.

US Fish and Wildlife spokesperson Bonnie Strawser said the fire's cause is under investigation. "We have been announcing it as a probable lightening strike but it was in actually three locations and so they're going to bring in a team to investigate the cause of the fire," said Strawser.

The fire has moved dangerously close to the Dare Bomb Range.  Military officials are evaluating the situation to consider the risk of the fire impacting unexploded ordinance.