"He was just shooting he had no intended target," said a text message from the woman, whose friend was the only person killed.
The woman spoke Sunday by BlackBerry instant messenger on condition of anonymity because she feared for her safety while the shooter remained at large. She said she was too upset to talk over the phone.
She described the Friday night party, which lasted into early Saturday, as a "typical fraternity party" with at least 100 people at the privately owned row house.
Students said the shooter was kicked out of the party when he refused to pay the cover charge.
The woman said she heard a fight erupt before the man was thrown out. Seconds later, she said, he returned with a handgun and started shooting as chaos erupted.
"Everyone was scrambling n stampeding. People were jumping out the two windows n all I cud smell was smoke n blood," the woman wrote. "The next thing I knew I opened my eyes n saw hell..blood n just panic."
The woman said was on the floor when the gunman stepped on her back and shot her friend Jessica Moore, a 19-year-old honors student majoring in psychology. Moore, who was from Disputanta, Va., died later at a hospital.
Authorities had not released the names of the four wounded people, whose injuries weren't considered life-threatening.
Two of the injured are 19-year-old women who go to Seton Hall, and one is a 25-year-old man who attends the New Jersey Institute of Technology. The other is a 20-year-old man from New York who is not a student.
East Orange police were following several leads but had not identified a suspect, spokesman Andrew Di Elmo said.
On Sunday, police had set up an electronic sign, the kind usually used to tell drivers of detours, to ask for help solving the house party shooting, which occurred just after midnight. The message advertised a $10,000 reward for information leading to an arrest.
The party was primarily for students at Seton Hall, a well-regarded Roman Catholic university with a gated campus in South Orange, about 15 miles from New York City. There are no sanctioned fraternities at Seton Hall and no fraternity houses.
The university, with its collection of red brick buildings tucked behind a wrought-iron fence, stands in stark contrast to the gritty neighborhood where the party was held a mile away. Just a block from the shooting site, the remains of a memorial for another recent shooting victim could still be seen.
There were at least five shootings in the area this summer, said Rabu Anderson, who owns a clothing store there.
"Some of it is gang violence, some of it is just plain ignorance," Anderson said.
East Orange resident Leon Drinks, who lives four doors down from the house where the party shooting occurred, said the violence has become much worse in the past couple of years. He said just after midnight he heard six shots - not an uncommon sound on South Clinton Street.
"I kinda laid low for a minute, then I heard the stampede of people on this side of the street and that side of the street," said Drinks, 54. "People were running in driveways and alleyways trying to get out of the mess."
Seton Hall, which has 10,000 students, knows about the dangers in some of the neighborhoods nearby and advises students not to leave campus alone.