The man who fatally shot ex-Jets running back Joe McKnight was released from custody early Friday without being charged.

Ronald Gasser, 54, shot McKnight in a fit of road rage outside New Orleans Thursday afternoon, police say. The investigation is ongoing.

A witness said that Gasser, who is white, shot McKnight, 28, more than once and at one point stood over him and said “I told you don’t f–k with me” before shooting him again. McKnight was not armed, police say, and Gasser remained at the scene after the shooting and gave his gun over to police.

Former Jets running back Joe McKnight was killed Thursday.

Gasser’s family said that they couldn’t believe that the telecommunications expert was capable of such an act.

“He’s the best guy, the most generous guy,” Gasser’s sister, Sharon Weileman, told NOLA.com. “I have no idea what happened. I can’t even talk right now.”

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“I’m speechless at the moment,” Gasser’s daughter, Candice Gasser-Bua, told NOLA.com. “I’m still trying to wrap my head around what happened.”

Gasser, residents told NOLA.com, moved into his father’s house in Gretna, La., about 15 years ao. He continued to live in the one-story brick house following his father’s death last year. Locals, who declined to be identified, said that Gasser lived alone in the home.

Ronald Gasser (seated) leans against his vehicle in in Terrytown, La., as Joe McKnight is treated to the right.

“He seemed to be a loner,” one resident told NOLA.com. “I never saw anyone else coming or going out of there.”

Antonio Cromartie, McKnight’s former teammate with the Jets, was dismayed to learn that Gasser was released without being charged.

"I don’t get it. How in hell do you release someone who killed my brother, my friend a father a son a brother without charging him. Bull Crap," he tweeted.

"You tell (me) how can a man murder someone go get to sleep in his bed at night," Cromartie added. "But my brother can’t. What the hell am I to tell my nephew."