Authorities are investigating a shooting at I-29 Speedway in Pacific Junction, Iowa, that resulted in the deaths of two Omaha men, 28-year-old Marcus Johnson and 27-year-old Charles Williams. The incident occurred just before 9 p.m. on Saturday during a car show and music festival. Witnesses reported not hearing gunshots and were only aware of the situation when police arrived. Investigators are searching for at least three suspects who were seen fleeing in a black Mercedes sedan. The Mills County Sheriff's Office is asking for the public's help with any information related to the shooting. The Omaha Police Department's helicopter has been deployed to assist in the search for the suspects.