The Delaware Attorney General's Office announced the indictment against John Wallace-Bey, who officials say voluntarily left work on the morning of June 16 after an argument with 19-year-old interns Ethan Hillman and Jayden Ellis.
All three were participating in a six-month IT internship program run through Code Differently, an external organization based in Christiana.
Christiana Care incoming CEO and president Jenn Schwartz said no concerns had ever been raised about Wallace-Bey before that day. She emphasized that he was not disciplined or sent home after the disagreement.
"He was not sent home, not fired, or disciplined in any way. Mr. Wallace-Bey was expected to return the next day for work," Schwartz said.
Attorney General Kathy Jennings said Wallace-Bey instead returned to Wilmington Hospital around 3 p.m. that afternoon.
"Around 3 o'clock that same afternoon, Wallace-Bey returned and confronted both victims in the basement of the Wilmington Hospital before withdrawing a firearm and shooting each victim one time," Jennings said.
Hillman was killed in the shooting, while Ellis remains hospitalized.
Schwartz said Wallace-Bey used his valid employee badge to re-enter the building. In response to the shooting, ChristianaCare has expanded weapons screening to all employee entrances.
The interns had been assigned that day to an administrative area of Wilmington Hospital for a scheduled IT project, Schwartz said.
"After the shooting, Wallace-Bey subsequently fled through the hospital's main entrance and traveled to the Wilmington train station, where he boarded a train, a SEPTA train, into Philadelphia," Jennings said.
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Initial information from police sources indicated Wallace-Bey drove from Wilmington to Philadelphia in a Toyota RAV4 and that police used license plate readers to track him, before arresting him as he attempted to catch an Uber.
The vehicle was towed from the scene of his arrest in the Olney section of Philadelphia. Delaware officials declined to comment further on that part of the case.
"I know there are still many questions unanswered, some of which may never have answers," Jennings said.
Wallace-Bey remains in custody in Philadelphia while awaiting extradition to Delaware. His extradition hearing is scheduled for June 29.
Officials also said the firearm used in the shooting has not been recovered, and Jennings said her office is "laser beam focused" on locating it.
Hillman's family has requested privacy. Ellis remains hospitalized but is making significant progress and is able to communicate with his family, Jennings said.