Police say 32-year-old Debora Ferreira, of Irvington, was shot in the face while she sat in her car on Halsey Street near William Street at about 3 a.m. Sunday. She had just returned from a night out with co-workers.
The victim has been employed by the Essex County Corrections Department since July, 2007.
Ferreira is the mother of a 1-year-old daughter. Her family said it was one of the first times she had been out since the birth of her little girl.
Acting Newark Police Director, DeMaio, said the department is working with the task force to bring closure to this "horrific act of violence."
Acting County Prosecutor Carolyn Murray says a motive for the shooting is unknown.
She declined to provide further details on the incident, which is under investigation by her office and Newark police.
The Essex County Crime Stoppers and the New Jersey state PBA have each offered $10,000 rewards for information in the case.
Anyone with information is asked to call 1-877- 847-7432. All calls will be confidential.
(The Associated Press contributed to this report.)