One person was killed when a small plane crashed on the highway in the northern suburbs of New York City Thursday night, according to police.The plane came down in the median of Interstate-684 near Exit 2 in Harrison near the Westchester County Airport around 7 p.m., according to New York State Police.Exit 2 is the exit for the airport.Exit 2 is the exit for the airport.Police said two people were in the plane and one of them died.No information was provided on the second occupant.The highway was closed in both directions after the crash, causing major traffic delays.Police are advising motorists to avoid the area.This is a developing story.Check back for more updates...