The father of a football player who was tragically killed on Sunday, when a gunman opened fire on the campus of the University of Virginia, has revealed his final words to his son.

Sean Perry is the father of D’Sean Perry. His son, a linebacker for the university’s Cavaliers, is one of three football players who were killed on Nov. 13. The other victims were identified as Lavel Davis, Jr. and Devin Chandler. Two other students were also wounded.

Authorities identified the suspected gunman as Christopher Darnell Jones Jr. CNN reported that Jones was on a bus with the students who were returning from a class trip to Washington, D.C., when he opened fire near a campus parking garage.

Sean told CBS News that his last time hearing from his son was on Saturday around 9 p.m. The following day (Nov. 13), he texted his son a clip from the previous day’s football game against the University of Pittsburgh. He wrote, “Keep on working,” but he never received a response.

The grieving father said he knew something was wrong when he texted his son around 11 p.m., “Yo good up there?” and it too went unanswered.

In since-deleted tweets, Sean wrote, “I know my son was calling for help. I couldn’t help my son. I know he was calling somebody.” In another he said, “God has the ultimate last word. D’Sean rest easy my [son]. Your journey here has been nothing [but] amazing son. We always knew you were special & God lend you to us. You definitely finished what you started out to do.”

On Wednesday (Nov. 16), WRIC-TV reported that a witness observed the football players as they were shot. The individual said there was nothing random about the suspect’s actions. Instead, it seemed he was “targeting certain people.”

In the wake of the tragedy making headlines, the suspect’s father, Christopher Darnell Jones Sr., spoke out. “He said there were some people there who were giving him a hard time, but he still was upbeat, and he was positive,” said Jones Sr. about his last encounter with his son. He continued, “I don’t know what happened between then and now to cause this to happen.”