An adult son of the 75-year-old Springfield man who was fatally shot Tuesday has been charged in a warrant with his slaying, Fairfax County police said late Wednesday.

Police were searching for Richard Hanson, 53, who was charged with murder in the death of Gary P. Hanson, a retiree who lived with his wife and two sons.

His whereabouts were unknown, said police spokeswoman Shelley Broderick.

She did not comment on what led police to issue the warrant against Richard Hanson, whom police had said earlier Wednesday was not considered to be a suspect.

Richard Hanson suffers from health problems and requires medical attention, Broderick said, but police did not elaborate on his condition.

He was described as 6-foot-1 with brown hair and brown eyes, and police said he might be driving a green, four-door 1998 Saturn with Virginia license plates.

The elder Hanson was found dead after officers responded to his home for a call about a person who was shot, police said. The results of an autopsy performed Wednesday were not yet available.

Many details about Gary Hanson’s death remained murky.

Police said they were called to the home in a quiet Springfield neighborhood about 6 p.m. Tuesday, but they would not say who placed the call.

Susan Piskor, 44, who lives nearby, said she was making dinner when she saw four police officers carrying rifles walk up her front yard Tuesday evening.

The police told her and her neighbors to stay inside and lock the doors and haven’t updated them since, she said.

“This is not what you expect to see and hear in this neighborhood,” Piskor said.

Chancellor Way is home to a mix of mostly older residents and some younger families.

Neighbors described the Hansons, who live in the 7600 block, as friendly, likable people with a beautifully kept home.

Gary Hanson had suffered a stroke in recent years and was less active in the neighborhood, neighbors said.

His wife often takes walks around the block and is known for the flowers in her garden, particularly her hydrangeas.

John Cover, 77, who lives next door to the Hansons, said neighbors often joked that all she had to do was drop a flower on the ground and it would bloom.

Hanson and his elder son mostly kept to themselves, Cover said, and the two enjoyed golfing at a nearby course.

Cover said Hanson’s wife and younger son were staying with neighbors.

They could not be reached for comment.

On Wednesday afternoon, police continued to block off the area outside the Hansons’ home, neighbors said. They said several police cars remained at the scene.

“It’s a total shock. You wouldn’t think that there were any issues with that family,” said Kathie Lawson, 63, who has lived down the street from the Hansons for the past 30 years.

Staff researcher Magda Jean-Louis contributed to this report.