JACKSONVILLE, Fla. -- A man who pulled the trigger, fatally shooting a 17-year-old early Monday, said he acted in self-defense.

Investigators said 28-year-old Robert Brown told them his car was being followed by another vehicle with several people inside and that he thought they wanted to rob him.

Detectives with the Jacksonville Sheriff's Office continue to investigate the fatal shooting that took place in the 7000 block of Old Kings Road South on the Southside.

Homicide investigators said Brown thought he was being followed and pulled into the parking lot, followed into the parking lot by three people in a minivan. When they got out of the van and approached Brown's car with a gun, he shot one of the subjects in the chest, police said.

"It was either him or me," Brown told Channel 4. "There was not even time to think twice. There was no time. They were strictly about their business. I needed to try and get up out of this."

Brown said he was afraid he was going to die Monday morning and that was why he fired his gun, hitting Tommy Lee Kennedy.

"I looked in the rear view mirror, I see some lights blocking my car in and I see the passenger door open and the sliding door open. Two dudes hopped out, one went directly to my window with a gun, arm pointed straight," Brown said. "You know, God said it isn't my time to go right now."

Police said there was an exchange of gunfire at the scene.

Kennedy died at the scene, and two other young men fled the scene, according to police.

"We don't know what happened regarding the other two people -- we know the other two people fled in a van," Jacksonville Sheriff's Office Sgt. Derrick Lewis said.

Authorities said that they are looking for a dark van with tinted windows.

Kennedy's sister, Tamika Kennedy, and the teen's friends said they couldn't understand why their loved one was killed.

"He is a good person. He takes care of his responsibility, I mean," Tamika Kennedy said. "My brother never meant to hurt nobody."

Police took Brown downtown for questioning and he was later released.

Anyone with information about the shooting is asked to call Crimestoppers at 866-845-TIPS.

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