NASHVILLE, Tenn. -- Multiple media outlets are reporting that Jerald Wayne Mills, frontman of the Wayne Mills Band, has died after being shot during a bar room altercation early Saturday morning.

, Mills got into a verbal altercation with the owner at the Pit and Barrel bar in Nashville just before 5 a.m.

, witnesses said Mills began smoking a cigarette in a non-smoking area of the bar, which prompted an argument with the bar's owner, Chris Ferrell.

Those witnesses said Mills and Ferrell were friends.

Ferrell told police he shot Mills in self-defense. Authorities are investigating those claims. Ferrell has a valid handgun carry permit. The Tennessean reported that Ferrell was back at the bar Saturday afternoon but declined to speak with reporters.

Mills was taken to Vanderbilt University Medical Center, where he was initially listed in "extremely critical condition."

The Wayne Mills Band announced Mills' death via its Twitter and Facebook accounts around 7 p.m. Saturday, saying "Word is Wayne has passed. God be with us all in this tragedy." Police confirmed Mills' death around 10:30 p.m. Saturday.

Mills, who was

and played football for the University of Alabama before focusing on his music career, played regularly at venues throughout his home state, including the Flora-Bama.

is generally described as "outlaw country," with influences from George Jones, Waylon Jennings and others. He leaves behind a wife, Carole, and a young son, Jack.