The accident happened at Olivers Mount racecourse in Scarborough, where the Gold Cup Qualifying is being held today.
A statement from Olivers Mount Racing this afternoon said: "Thank you all for your patience this morning. We had an incident during Gold Cup qualifying that involved one rider and three spectators. "We are now cleared for racing again and riders are back on circuit. "Thank you to the marshals, medics, air ambulance crew, stewards, officials and spectators who assisted us this morning."