Dayvon Green, Stephen Rane and Neal Oa didn't know one another before becoming roommates last fall, sharing a modest split-level house in a subdivision across from the University of Maryland, College Park.
But Oa came to regard Green as a friend, making Tuesday's events at the house even more shocking. Early that morning, Green opened fire, shooting Oa in the leg and killing Rane, police said.
The violence stunned the community and those who knew Green. Police said the 23-year-old graduate student who had interned at NASA set fires in and around the home to lure his roommates outside before he shot them. Green then killed himself.
Oa, who has been released from the hospital, was resting at his family's home in Frederick County on Wednesday and is expected to return to school once he is healed. The 22-year-old fled two houses down, where neighbors hid him in the bathroom.
Oa's stepfather, Chris Merz, said detectives told him Oa was right to follow his instincts and run, rather than stand his ground.
"He's a strong, smart boy so we're confident he'll come through that OK," Merz said. "But it's a scary moment to be literally running for your life. If you don't run, you don't live. And thank God he did."
The campus has seen violence, including the 2011 killing of a student in what was described by police as a drug-related robbery two streets over from where Green, Rane and Oa lived on 36th Avenue. But College Park students said they found the randomness of the shooting particularly unsettling.
"Every couple of months we hear about a shooting at a school," said student Jan Abmzom, 25. "It's not like I'm anxious, it's just a feeling of insecurity, like it could happen to me one day."
The campus mourned 22-year-old Rane, a senior English major who had graduated in 2009 from Centennial High School in Ellicott City. His mother and stepfather work in the entomology department at the university.
Meanwhile, detectives canvassed the house again on Wednesday to find clues they may have overlooked. Still unknown is why Green became violent.
Friends of Green said they did not see any warning signs in the promising engineering student. According to Prince George's County police, Green was being treated for an unspecified mental illness for at least a year.
Police said he stuffed into a backpack a baseball bat, a machete and a semiautomatic Uzi he'd bought just weeks before and stuck a 9 mm handgun into his waistband before he confronted his two roommates.
Merz said his stepson told him he ran from Green knowing it was for his life. Shot in the leg, Oa fell, then got back up and fled.
He escaped into a neighbor's house and called an ambulance and then his family. As paramedics took Oa to the hospital, his family rushed from their home to be by his side.
When they arrived — still not sure of his condition — detectives were interviewing Oa and they had to wait for them to finish, Merz said.
"Sure there's a sense of relief knowing he was shot and he survived it," Merz said. "He's a light in our life, and to lose him would just be devastating to us."
His injuries turned out to be relatively minor, a single bullet wound to the leg. Oa was discharged around noon Tuesday, Merz said, and was resting at home, able to walk without crutches. Doctors might not remove the bullet, Merz said.
Oa did not wish to speak publicly.
The roommates socialized but were not especially close, Merz said. At least two other people live at the house. Two are in the Air Force and are rarely around, Oa's stepfather said.
Neighbors said there were parties at the house but not large ones.
Green was smart but "a little different" and had moods that were up and down, Merz said.
Green, a Baltimore-area native, graduated from Morgan State University, where he excelled.
Chinedu Nwokeafor, a 20-year-old junior at Morgan State, said Green was an important mentor to him two years ago, when he was a freshman struggling with his course work and Green was a senior resident assistant in O'Connell Hall, the campus dorm he lived in.
Nwokeafor said he met Green one night near the front desk of the dorm. Green told him he noticed he didn't go to his classes, and asked him about his frustrations.
"He literally helped me out in everything I was doing," said Nwokeafor, who is from Bowie. "He sat there for almost two hours advising me on what I could do, what teachers I could talk to. He told me if I needed anything, I should come talk to him, which I continued to do."
Nwokeafor, who is now a speech communications major, was at the time studying engineering, and Green routinely helped him with his course work, he said. Green even took Nwokeafor along to an event held by NASA.
"He exposed me to many experiences I will never forget," Nwokeafor said.
When Nwokeafor came across a news story online on Tuesday naming Green as the alleged shooter in College Park, he "couldn't believe it," he said.
"I've only known him as very, very calm, soft-spoken, somebody who's not anything close to violent," Nwokeafor said. "I still believe he's that kind of person."
The last time the two touched base was sometime last year, Nwokeafor said.
By Wednesday, police had not said which mental illness Green suffered from, or what his motive might have been. Friends of Green did not know, either. Police did not find a suicide note.
Clinton Coleman, a Morgan State spokesman, said the university is cooperating with law enforcement to provide all records requested of them, but that he could not comment on whether Green had received mental health services at the university. College Park officials said he had not been treated for mental illness at their health care facilities.
College Park students on Wednesday said they were shocked by the crime, even as they noted a recent rash of armed robberies and the usual need to be vigilant off campus.
Some students wondered why they were not told more by the university about what happened and hoped campus police would step up patrols.
Marvin Mathew, 22, said the whole campus is mourning and thinking of the families.
"Our hearts go out to those families," he said. "It could have happened anywhere, to anyone."
Green bought his weapons legally, police said. Current law does not prevent those who seek treatment for mental illness from buying a gun unless they have been committed to a psychiatric institution for more than 30 days.
Despite his stepson being a victim of gun violence, Merz said he's not sure stricter laws would have prevented what happened, pointing out that Green was also carrying a machete.