Find this semi rig by using tips and surveillance video. But as ken mentioned earlier, this driver might not even realize that he or she collide with the motorcycle. The motorcycle rider, a 61year old man was found in the middle of the street, killed when his motorcycle crashed. Heavy traffic came to a halt as the chp closed the stretch of mission boulevard at 1 15 this afternoon. What caused the crash is a mystery that the chp is still trying to unravel tonight. A big rig that was towing two chrome colored tanks, its potentially a vehicle that left the scene. Reporter the chp says witnesses told them the big rig collided with the motorcycle, and never stopped. Now, investigators are searching for the silver big rig tanker. The problem is that the street gets a lot of truck traffic. The chp says its more dangerous because this particular stretch of roadway is also under construction right now. Reporter construction barriers have created another hazard that could have been a factor. Its