EVANSVILLE, Ind. — Police are investigating a fatal weekend shooting at a popular Franklin Street bar as a possible self defense case.

The shooting took place at sportsman's Grille & Billiards around 12:45 a.m. Sunday. Of-duty officers working at the bar found Laren Hall, 23, shot in the alley behind the establishment. He was taken to a hospital where he was pronounced dead.

Multiple witnesses at the scene reported seeing a group of five or six men sprint toward two men at the back of the bar, EPD spokesman Sgt. Jason Cullum said at a news conference Tuesday afternoon.

One witness, an employee on break at the restaurant, reported seeing a man fall to the ground and being beaten up before shots were fired.

Police believe Hall was one of the men involved in the alleged assault.

Surveillance video at nearby businesses corroborate witness accounts of the events leading up to Hall's death, Cullum said, but there is no video of either assault or shooting.

The coroner's office earlier said it would conduct an autopsy on Hall's body Monday afternoon. Vanderburgh County Coroner Steve Lockyear said Hall died of single gunshot wound to the chest.

At the scene, a responding officer found a man with the gun. The officer disarmed the man, who had injuries to his face, and detained him without incident, Cullum said.

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A second man, 27-year-old James Bales of Shoals, also had apparent injuries. Police are not releasing the identity of the man with the gun because he is the subject of an ongoing investigation. The man has not spoken to police, invoking his fifth amendment rights, Cullum said.

No criminal charges have been filed, and the investigation is ongoing. Police are encouraging any potential witnesses to come forward