New York ? A 7-year-old boy was found dead in the water of a boat ride at a historic amusement park Wednesday after he didn’t emerge from a tunnel, authorities said.

The boy apparently climbed out of the boat and got caught in the conveyor belt of the Ye Old Mill, a boat-in-the-dark ride, at Playland in Westchester, just northeast of New York City.

The ride that killed the Norwalk, Conn., boy, whose name was not released, is “one of our most benign,” County Executive Andrew Spano said at a news conference.

The ride consists of 14 boats propelled into a tunnel. The water is 2 1/2 feet deep at its deepest, and instructions tell riders to stay seated and keep their hands inside their boats.

The boy, who was at the park with his mother, got on the ride by himself after passing the 42-inch height requirement for riding alone and was the only person in his boat, Spano said.

Playland, a National Historic Landmark, opened in 1928. The amusement park scenes in the movie “Big,” starring Tom Hanks, were filmed there.