The youngster, whose name was not released, was recovering Thursday from multiple injuries to his leg.
"He had cuts all over and he wasn't moving," witness LeRoy Mace, 40, of Brooklyn, told the New York Daily News. "He was on the tracks for at least 20 minutes before they pulled him off."
An executive with Deno's Wonderwheel and Amusement Park told the newspaper the child apparently became frightened while riding the so-called kiddie roller coaster, wiggled under the lap bar and jumped out of the car before it stopped at the completion of its trip.
The child's older sister was in the car with him and was treated for a minor leg injury. Their mother had been waiting for them at the end of the line and witnessed the incident, the Daily News said.
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