A man was seriously injured Saturday afternoon when involved in a crash with a race cart type vehicle on the lot of Auto Pros along SR145 in Walnutport. The incident was first reported just after 2 p.m. When police and emergency personnel arrived on scene they found a man lying on his back in the lot apparently ejected from the vehicle. Reports from the scene claim the victim may have not been wearing a helmet nor a seatbelt. He was treated at the scene by Northampton Regional paramedics and transported to an area trauma center. Lehigh Township police are investigating the incident.