Fairfax County police said Wednesday they are investigating the death of a 75-year-old Springfield man as an apparent homicide.

Gary P. Hanson was found dead around 6 p.m. Tuesday in his home, in the 7600 block of Chancellor Way, police said. They said officers had responded to a call about a person who was shot, police said. 

Officer Shelley Broderick, a Fairfax County police spokesperson, said detectives are trying to find Gary Hanson’s son, Richard, 53, who lived at the residence where his father was found dead.

Broderick said Richard Hanson is not considered a suspect in his father’s death. Police, who said Richard Hanson suffers from some medical issue but did not elaborate, said they are concerned for his well-being and have listed him as a missing and endangered adult. 

Richard Hanson may be driving a 1998 green, four-door Saturn with Virginia license plates. The investigation is ongoing.

Broderick said police remained on the scene until after 10 p.m. Tuesday. It was not clear who called the police to report Hanson had been shot.