Allen Sessoms, the university president, said the shooting did not involve a gunman attacking at random or a terrorist, WCAU in Philadelphia reported.
"This is a case of our own students making really poor decisions and acting incredibly badly," he told reporters at an afternoon news conference.
By Friday evening, police were questioning two people identified as "persons of interest," The Baltimore Sun reported.
One of the wounded students, Shalita Middleton, 17, of Washington -- who was shot twice in the abdomen -- was in serious condition. The other, a 17-year-old male, was hit in the ankle.
The academic year at Delaware State opened with tragedy this year. Three students were killed and a fourth wounded in August in Newark, N.J.
The campus was partially locked down Friday. Students were supposed to remain in their dormitories, but parents were allowed in to take sons and daughters home for the weekend.