Slippery conditions at a New Jersey racetrack might have caused the starting gate car to skid out of control and into six horses and drivers Friday afternoon.The bizarre accident occurred when field of seven trotters was entering the first turn on Freehold Raceway's half-mile oval during the fifth race. Video replays show the car sliding toward the infield, doing a 180-degree turn and facing the field head on. Only the lead horse, Civic Duty driven by James Clarry, cleared the car, which has large gates on either side that are folded back in after a race starts.The second horse, driven by Hall of Famer Catello Manzi, and the sulky were the first to crash into the car and into a gate that was still fully extended, according to nj.com."We don't know what happened. It was definitely a freak mishap. Something I've never seen in 40 years in racing," said Freehold Raceway director of facing and race secretary Karen Fagliarone.Track conditions were not an issue for the first four races of the day, Fagliarone said, adding that there was no ice reported on the track. However, Freehold immediately canceled its final six races of the day following the accident.Track superintendent Michael Fagliarone and Freehold general manager Howard Bruno both refused to comment. The driver of the starting gate car, Robert Blum, could not be reached."The initial inspection was that the horses are all okay. Four of the drivers have been transported to Jersey Shore Medical Center" in Neptune, said Fagliarone, who did not know the specific conditions of the drivers.The track was slick, but temperatures at the central N.J. track hovered around 37 degrees at race time. Freehold officials declared the fifth race a no-contest and cancelled the final six scheduled races.