JACKSONVILLE, Fla. -- A 26-year-old man died Sunday night after he was shot inside a Mandarin convenience store and homicide detectives are trying to determine if the shooting was in self defense.

Police responding to a report of a gunshot at the BP gas station at the corner of Old St. Augustine and Losco roads about 9:45 p.m. found Isaiah Williams lying on the ground. He transported to Shands-Jacksonville Medical Center, where he died a shot time later.

The store clerk told Channel 4's John Dunlap that the shooting followed a confrontation that began with Williams cursing a man in line behind them.

"He went out and he came back with a friend," BP manager Reddy Kandala said. "That time, there was a fight."

Kandala said the shooter, whose name was not released by police, told Williams and his friends he had a gun. Kandala said Williams left the store again, but when he entered for a third time, he was shot.

The gunman is cooperating with police and the entire incident was recorded by surveillance cameras. Police and the state attorneys office will review the evidence and witness statements to decide if the shooting was in self defense or if the gunman should be charged with a crime.