A sixth person has died after being shot by a former NFL player at a South Carolina home last Wednesday. Robert Shook, a 38-year-old air conditioning technician, was shot in the driveway of the Rock Hill, South Carolina, home where he had been working, the York county sheriff said. He died from his wounds on Saturday. The gunman, whom officials identified as 32-year-old Phillip Adams opened fire at the home of local doctor Robert Lesslie, killing Lesslie, 70, his wife Barbara Lesslie, 69, two of their grandchildren, nine-year-old Adah Lesslie and five-year-old Noah Lesslie, and James Lewis, 38, another air conditioning technician, the county sheriff’s office said. “We are all heart broken,” the men’s employer GSM Services posted on Facebook on Saturday. Adams, who left the NFL more than five years ago, killed himself at his home a short distance from the murder scene. Investigators have not identified a motive for the shootings. “We have probably more questions than you do right now,” York county sheriff Kevin Tolson told reporters on Thursday. There was no indication that Adams had any relationship with Lesslie or his family, Tolson said. The gunman’s father, Alonzo Adams, suggested the shooting outburst was the result of injuries his son sustained during his football career, in which he played as a defensive back with five teams, finishing with the Atlanta Falcons in 2015. “I think the football messed him up,” he told WCNC-TV in Charlotte, North Carolina. Phillip Adams’s brain is now being examined for possible degenerative disease that has been shown to cause violent mood swings and other cognitive disorders in some athletes and members of the military. With the Oakland Raiders, he had two concussions over three games in 2012. Whether he suffered long-lasting concussion-related injuries wasn’t immediately clear. Adams would not have been eligible for testing as part of a broad settlement between the league and former players over such injuries, because he hadn’t retired by 2014. Asked to comment, an NFL spokesman said, “Our hearts go out to the families and friends of the victims of this devastating tragedy.”