Police are investigating the crash that caused the death of NASCAR driver Jason Leffler on Wednesday night at a New Jersey dirt track event. The 37 year-old driver was killed when his car hit the wall and rolled several times at the Bridgeport Speedway in Logan Township. Officials will see if a mechanical failure could have contributed to the crash. The accident occurred during the second lap of the first heat of racing, which forced the cancellation of competition for the night. The speedway is scheduled to conduct a racing event on Saturday, but it could not be confirmed when the track will re-open.