(CNN) -- Two university students gunned down Sunday were unintended bystanders and not the targets of the people who opened fire at the University of Central Arkansas, a prosecutor said Tuesday.
Student Ryan Henderson, 18, was shot to death on the UCA campus Sunday, according to police.
Police are still trying to figure out the motive for shooting, said Marcus Vaden, prosecuting attorney for the 20th Judicial District of Arkansas.
Vaden did not say whom the shooters were targeting.
Four suspects were arrested after the shooting and were charged with two counts of capital murder and one count of attempted murder Tuesday, a prosecutor said.
The suspects also were charged with eight counts of committing a terroristic act and other weapons charges in the Sunday night shooting, Vaden said.
A third man, who is not a student, was wounded in the shooting.
The suspects are Kawin Brockman, 19 of Conway; Kelsey Perry, 19 of Morrilton; Mario Toney, 20 of Little Rock; and Brandon Wade, 20, of Lake Village, the university said.
Police have released few details on the suspects other than saying that they are not university students.
"It does not seem at this time that it was a random act," police Lt. Preston Grumbles said Monday, adding that police are "unsure of the precise motive." He said there was "no indication" that the shootings were gang-related. Watch police describe the shooting »
Ryan Henderson, 18, of Little Rock and Chavares Block, 19, of Dermott were killed in the incident outside a university dormitory on Sunday night. Block was a sophomore pre-engineering major. Henderson was a freshman who had not declared a major.
First State Bank of Conway established an account Tuesday to accept donations for the families of the two teenagers. Donations to the Block-Henderson Memorial Fund will be passed on to the two families, the university said.
A third victim, Martrevis Norman, was treated at a hospital and released on Sunday. He is not a student at the university, said Lt. Rhonda Swindle of UCA campus police.
"This is something you pray never happens," a visibly upset interim University President Tom Courtway said Monday. "But it happened."
The shooting prompted a campus lockdown and the cancellation of Monday classes. The university, in Conway, has about 12,500 full-time students.
CNN's Marylynn Ryan contributed to this report.