A jockey has died after falling off his horse during a race this weekend at Blue Ribbon Downs in Sallisaw, Okla.

Racetrack General Manager Blaine Storey says 58-year-old Mark Pace of Devine, Texas, died Sunday after falling off his mount, Reep What You Sow, during the first race.

The Oklahoma Horse Racing Commission is investigating. The track is owned by the Choctaw Nation of Oklahoma.