The accident happened during the 8th race.
A jockey is hospitalized in stable condition after a spill involving seven horses and riders at the Hollywood Casino at Charles Town Races.
Chief Steward Danny Wright says 43-year-old jockey Anthony Mawing of Kearneysville, W.Va., was kept overnight for observation but has no life-threatening injuries.
The accident happened during the eighth race Wednesday night, when a horse named Sharp Beauty broke down on the far turn under jockey Carlos Marrero.
Sharp Beauty was later euthanized.
Wright says six riders were thrown from their mounts, but they all walked away unhurt.
Wright says the accident had nothing to do with the condition of the track, owned by Pennsylvania-based Penn National Gaming Inc.
Miss Fifty was the only horse to finish the race.