Authorities responded to a shots fired call shortly after 11 p.m. at a home in the 16000 block of Forrest Avenue.
Deputies found two male gunshot victims inside a home, and one of those victims, identified as 60-year-old Don Grigsby, died at a hospital.
Investigators say a gunman entered the home and shot both men. The second victim, identified as 37-year-old Gregory Wilburn, suffered non-life threatening injuries and is expected to survive.
Officials don't believe any property was taken, and there was no suspect description available.
The motive for the shooting remains under investigation. Officials said it did not appear to have been a home invasion.
"It does appear that the suspect entered the home, likely uninvited, and then the shooting occurred, but typically we associate home invasion with suspects that come in and injure and rob the victims, and in this case that did not happen," explained Cindy Bachman of the sheriff's department.
Anyone with information is urged to contact the Homicide Detail, Detective Mark Green at (909)387-3589. To remain anonymous, call the We-tip Hotline at 1-800-78-CRIME (27463).