NEW YORK -- A racehorse kicked through the floor of a trailer on an expressway on Wednesday, injuring itself and snarling traffic before being euthanized.

Images: Horse Injured During Ride

A motorist saw the horse's hoof sticking through the trailer around 4 p.m. and got the attention of the trailer's driver, who pulled over to the side of the Cross Bronx Expressway.

Traffic was stopped as a veterinarian examined the horse.

The horse, a 3-year-old thoroughbred gelding, was euthanized around 6 p.m. at the Belmont Park Raceway in Elmont, said Joe Pentangelo, a spokesman for the American Society for the Prevention of Cruelty to Animals.

Three other horses in the trailer were uninjured.

The trailer was pulled off the highway with the horses still inside, the NYPD said.

The crash caused authorities to block two lanes and led to heavy traffic stretching from the George Washington Bridge to Webster Avenue.

Pentangelo said the horses were being transported from Gent, N.Y., to the raceway. He wasn't sure who owned the animals. The ASPCA was investigating.

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