Star, N.C. — A 50-year-old man accused of shooting four men at McBride Lumber Co. in Montgomery County Friday morning died early Saturday of injuries he suffered after turning the gun on himself. 

According to the Montgomery County Sheriff's Office, Ronald Dean Davis, of 103 Telegraph Lane, died early Saturday at the University of North Carolina at Chapel Hill Medical Center. 

After the shooting, deputies found him at his home with a self-inflicted gunshot wound to the head. He was still breathing and was transported to FirstHealth Montgomery Memorial Hospital, before being airlifted to UNC.

Three of Davis' victims died Friday, while a fourth remains in critical condition. Officials have not released any names. 

Montgomery County Sheriff Dempsey Owens said Friday that Davis targeted his victims when he entered the plant just after 6 a.m. and started shooting with a 12-gauge shotgun. Sixteen people were at the plant at the time of the shooting. 

"He knew who he went after," Owens said. 

Authorities found a six-page letter at Davis' house. The contents, which "rambled on," are under investigation, Owens said. According to police, Davis did not have a criminal record. 

Donnie McBride, who owns the lumber company, said Davis had worked for him for about a decade and that one of the victims was Davis' cousin.

"I never dreamed anything like this would happen," McBride said.