The incident happened happened in May in the Paladium Club.
A popular reggae artist was performing when a gunman opened fire, killing a fan and injuring a guard.
Amid the chaos, the shooter escaped.
"There were multiple people holding up their cell phones, recording the event," Essex County Prosecutor's Office Detective Carlo Olmo said. "And we believe that some of the images or the video obtained on the phones may help us in our investigation."
Police are hoping that video will help catch the suspect.
Get Eyewitness News Delivered