Dumas Police Chief Keith Finch provided the increased number of casualties but said it wasn't immediately clear how many kids had been hurt, ABC News reported.
One person was in custody, although there may have been multiple shooters, Finch told reporters.
State troopers were dispatched at around 7:25 p.m. to Dumas, located about 90 miles (144 kilometers) south of Little Rock, following a report of gunfire outside a local business where the car show was underway, Arkansas State Police spokesperson Bill Sadler said.
The car show is part of a community event held each spring to raise funds for scholarships and school supplies, according to the website of the Delta Neighborhood Empowerment Youth Organization.
Wallace McGehee, the car show's organizer, expressed condolences to the victims' families and the community.
Additional information, including conditions of the wounded, wasn't immediately available.
RHM/PR