"We extend our most heartfelt condolences to Jessica's family and friends," Seton Hall Interim President Gabriel Esteban said in a statement. "Please know that we share in your grief and that we will be praying for you in the difficult days ahead.
"As we move forward from this senseless tragedy, we will look for peace and healing through our faith, and through the love and support of friends and family."
Officials said the shootings occurred when a man who unsuccessfully tried to crash the party returned with a handgun and opened fire.
The incident occurred in East Orange -- about a mile from the Seton Hall campus -- at 12:17 a.m. Saturday during a party at a private residence, officials said. A man described as being in his mid-20s became involved in an altercation when he entered.
He left the house, rented by a graduate student, and returned moments later with the handgun.
The victims, two men and three women, were taken to University Hospital.
Four suffered non-life threatening wounds, said Cordero, who, like other officials, would not identify them. Hospital officials will not release their conditions, spokeswoman Stacy Newton said.
It wasn't immediately clear if the shooter, who was still at large Saturday afternoon, is a student. He is described as a black man, between about 5 feet, 11 inches tall, and 6 feet, 2 inches tall, and having a stocky build and a scruffy full beard.
Counseling services are being offered to Seton Hall students. A prayer service was scheduled for Saturday night.
Police were looking at surveillance video in the neighborhood for potential evidence.
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