A 23-year-old University of Maryland graduate student who had been suffering from mental illness shot and killed one of his roommates and wounded another before killing himself early Tuesday morning in College Park, authorities say.

Shortly before 1 a.m., police went to the 8700 block of 36th Avenue and found three men who had been shot.

According to a preliminary investigation by Prince George's County police:

Dayvon Maurice Green had set multiple fires in and around the backyard of the home. Two of his roommates went downstairs to see what had happened and found Green in the backyard. Green opened fire, hitting 22-year-old Stephen Alex Rane, of Silver Spring, several times and killing him. Also shot as he was running away was the other roommate, another 22-year-old Maryland undergraduate whose name had not been released Tuesday night. That roommate suffered non-life-threatening injuries. Green then returned to the backyard and shot himself.

Authorities said they recovered two guns from the scene, including a Smith & Wesson 9 mm semi-automatic pistol -- believed to have been used in the shootings -- found next to Green's body. A bag of weapons police found included a baseball bat, a machete, a loaded .22-caliber semi-automatic Uzi B rifle and ammunition.

Dayvon Maurice Green, 23, was a graduate-level engineering student from Rosedale, Md. Green obtained his undergraduate degree from Morgan State University in Baltimore and had been named a NASA student ambassador at the Goddard Space Flight in Greenbelt in 2011. Family members told investigators he had been suffering from mental illness for at least a year, and had been prescribed medication for the illness.
Fallen victim:
Stephen Alex Rane, 22, of Silver Spring, was expected to graduate from the University of Maryland this year with a double major in English and linguistics. He often made the dean's list.

Green legally purchased the Uzi on Jan. 18 at a gun shop in Silver Spring, authorities said, and the 9 mm appeared to have been legally purchased in the Baltimore area in 2012.

After speaking with Green's family, detectives learned he had been suffering from mental illness, police spokeswoman Julie Parker said. He had the illness for at least a year and had been prescribed medication for it, Parker said.

Green was studying engineering at Maryland and as an undergraduate had studied computer science at Morgan State University in Baltimore before coming to College Park. He had also been a student ambassador at NASA's Goddard Space Flight Center in Greenbelt.

The block in College Park where Green and his roommates lived is a residential street with a number of small houses, less than 100 yards from University Boulevard and bordering the school to the northwest.

Late Tuesday morning, police had cleared the crime scene. There was a blood stain on the road in front of the house where the shootings happened, and remnants of a fire could be seen in the backyard. An SUV in a neighbor's driveway appeared to have its back window shot out.

Chip Cobb, who lives next door to the house where the shootings occurred, said that when he heard the shots, he ducked in a corner of his room, curled up in a ball and waited for the gunfire to stop.

"It seemed like the thing to do," said Cobb, a 24-year-old graduate student in the English Department.

After the gunfire ended, Cobb said he checked to make sure his roommates were OK, went outside and noticed a fire in his backyard and one between his house and the one where the shootings happened. Cobb said he called 911.

"I'm grateful that I'm alive and my friends are alive," Cobb said.

Examiner Staff Writers Scott McCabe and April Burbank contributed to this report.