They describe the vehicle as straddling lanes, tailgating, and its headlights flashing and horn beeping.
One witness says the driver at one point tried to pass him on the shoulder of the highway.
Police are trying to piece together Schuler's trip from an upstate campground to the Taconic Parkway in Westchester County.
Once there, she drove the wrong way for nearly two miles before crashing.
Schuler, her 2 year-old daughter, and three young nieces were killed. Three men in the SUV also died.
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