BROOKLYN, Michigan — New Jersey state police said Friday that a mechanical problem was to blame for the dirt-track racing crash that killed NASCAR driver Jason Leffler. The state police released some findings from a not-yet-complete report on the June 12 crash at Bridgeport Speedway in Logan Township. The report finds that a torsion stop came off, causing part of the sprint car's suspension system to become lodged between a wheel and the steering system. As a result, the report found, Leffler was unable to control the car's steering as he came out of the fourth turn and spun out, slamming into the concrete wall along the side of the track. The report does not say how fast Leffler was going, but says cars in the race were averaging 135 mph and hitting 150 mph on straightaways. Blunt-force neck injuries were cited as his cause of death. The 37-year-old Long Beach, California, native was a two-time winner on the NASCAR Nationwide Series and a one-time winner in the Truck Series. Leffler, who had a 5-year-old son, raced in both the Daytona 500 and Indianapolis 500 over his 14-year career. He was a friend and protégé of Tony Stewart, who said last week at a race in Michigan that people should not blame track conditions for Leffler's death. “It was an accident. Just like if you go out and there's a car crash. It's an accident,” Stewart said. — AP