His weapon was recovered at the scene, authorities said, and he was expected to face numerous charges, including aggravated assault and weapons offenses. It was not known if the gunman was targeting a specific person or group.
Anthony Ambrose, chief of detectives for the Essex County Prosecutor's Office, said the shooting occurred around 10:15 p.m., causing crowd members to flee in panic. One bullet struck a man in the arm, and a Bloomfield police officer then shot the gunman once in the torso.
The wounded victim remained hospitalized Saturday at Clara Mass Medical Center in Newark, where he was listed in stable condition.
The gunman was taken to University Hospital in Newark, where he underwent surgery Friday night, but further details on his condition were not disclosed Saturday.
However, both men were expected to recover from their wounds, Ambrose said.
"The officer's quick response and professional actions helped avoid what could have been a worse scene here," Bloomfield Police Chief Mark Leonard told The Star-Ledger of Newark. "Initial investigations show he did the proper job."
The officer, identified only as a 15-year veteran of the force, was not hurt, and no other crowd members were injured.
The shooting will be reviewed by the county Prosecutor's Office, which is standard policy for police-involved shootings.