(CNN) -- At least four people -- three in North Carolina and one in Indiana -- were injured after weapons went off at gun shows Saturday, officials said, at a time when there's been renewed discussion about private gun sales at such shows.

Dixie Gun and Knife Show attendees bolted, with at least one woman wiping out in the frenetic scene, after gunfire rang out around 1 p.m., as seen on video captured by CNN affiliate WRAL.

Police later explained that a a 36-year-old man from Wilmington, North Carolina, was unfastening the case of his 12-gauge shotgun on a table near the show entrance when it accidentally discharged. The man planned to sell the shotgun at the show.

The bird shot ended up injuring three people. One was a sheriff's deputy, who suffered a slight injury to his hand and was treated and released at a local hospital before returning immediately to work, said Joel Keith, chief of police of the North Carolina State Fair.

A 54-year-old woman from Benson, North Carolina, was being treated a wound to her right torso at a local hospital, and a 50-year-old man from Durham, North Carolina, was treated for an injured left hand, Keith told reporters.

"I want to emphasize that this is an accident," Keith said.

That said, Wake County sheriff's investigators and the local prosecutor will determine whether to file charges against the gun's owner, authorities said.

Sheriff Donnie Harrison said he was unsure whether it was legal to bring a loaded gun on state fairgrounds. However, when the state fair is held in October, it is illegal to bring a loaded gun to the fairground because of the large crowds, authorities said.

"This is state property. That's something we're looking into," Harrison told reporters. "It's early right now."

The shooting prompted police to ban any private gun sales -- in which visitors bring their firearms to sell at the gun show -- for the remainder of the two-day show, which concludes Sunday, Keith said. He added there wouldn't be any private gun sales on fairgrounds for he indefinite future.

The gun show was closed after the shooting and will reopen Sunday. At that point, show vendors can continue to sell firearms, which are already secured inside the show, Keith said.

"If we thought if it was a problem or a hazard, we wouldn't have this show," Keith said about private gun sales at the show. "I'm sure there isn't anybody who hates this more than the guy who owned this weapon."

Meanwhile, in Indianapolis, a man walking out of the Indy 1500 Gun and Knife Show shot himself in the hand as he was loading his .45-caliber semi-automatic firearm, Indiana State Police said in a statement.

The 54-year-old Indianapolis man was sent to Wishard Hospital for treatment after being "slightly" injured.

"The investigation determined the shooting to be accidental, and no charges will be filed," police said.








4 Injured After Firearms Go Off At N.C., Indiana Gun Shows