It happened at about 12:40 p.m. on the Southern State Parkway westbound, west of Exit 32 in Oyster Bay.
New York State Police say 18-year-old Nicholas Hollifield, while driving a blue Chrysler, pointed the black BB gun at a driver after allegedly being tailgated.
Hollifield, of East Islip, was located on Carlisle Road in Wantagh by Nassau County police.
He was charged with criminal possession of a weapon and menacing.
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