Vincent Harrison, the off-duty NYPD officer killed in a hit-and-run on the New Jersey Turnpike early on February 28th, was pointing his gun at a woman who he crashed into and threatening her when a second driver ran him down, investigators have determined.

State police and prosecutors said Harrison, 25 and in his second year on the force, was driving a Chevy sedan south on the turnpike near the Newark International Airport, when he rear-ended a Ford SUV driven by a 26-year-old woman. They both stopped, and he got out of his car, walked to the other vehicle, the woman and her 2-year-old son inside, and began arguing with the woman. Harrison allegedly drew his gun, and at some point, sources told ABC7, he yelled something like, "You don't know who I am!" and "I can kill you right now!" over and over.

Stepping away from the woman, he backed into traffic and was struck by the driver of a passing Infiniti sedan. He was pronounced dead on the scene at 3:28 a.m., reported.

State police caught up to William Espinal-Mejia of Linden, New Jersey, and charged him with leaving the scene of an accident. He pleaded not guilty in court today and is being held on a $100,000 bond.

Espinal-Mejia's lawyer told the judge that he stopped after hitting Harrison, but drove off when he saw an approaching semi truck start to jackknife.

"It was just a very, very dangerous situation," Rotolo said. "He had his wife and cousin in the car, and he made the decision to leave."

Union County prosecutor Robert Rosenthal countered that Espinal-Mejia "didn't pull over somewhere further down and make a phone call. He didn't get off the highway and make a phone call. He didn't drive to a police station. He was not going to come forward with this."

Police found Espinal-Mejia at home, and after they settled on charges, he turned himself in at the Newark state trooper station on the turnpike on Monday evening. Rotolo said he expects his client to post bail.

Speaking to ABC7, Harrison's cousin Drexel Berry called the late officer a "genuinely nice guy. You didn't have to ask him for anything because he was already giving it to you. Justice should be swift. It should be swift because, from what I can see, there's no reason that this should've happened."