Two students have been taken to hospital following an early morning shooting on the campus at Delaware State University.
A female student was being treated for serious injuries and a male student was reported to be in a stable condition.
The campus has been closed down and students warned to stay indoors while police search for the gunman.
One suspect was still at large, officials said.
Carlos Holmes, DSU spokesman, said the female student appeared to have suffered serious wounds. "They could be potentially life-threatening," he said.
The male student's wounds were not as serious and he was in stable condition at a hospital.
"We have no imformation on the shooter. No suspect has been identified, " said Holmes.
"We have no way of knowing if he's left the campus yet."
"The entire population knows it now if they haven't slept through the whole thing," said Holmes.
Dover Police Department and other agencies are assisting the university police in the search for the gunman.