Officers and medics responded to the scene, a home near South 315th Street and 10th Avenue South, at about 7:30 a.m. after the man who pulled the trigger called 911 and said he had just shot his brother, said Cmdr. Stan McCall of the Federal Way police.
The victim was found with a single gunshot wound to the abdomen. He was taken to Harborview Medical Center for treatment.
A preliminary investigation found that the 911 caller, a 61-year-old Federal Way man, shot his 52-year-old brother-in law during a physical dispute, police said. The 61-year-old was taken into custody.
An elderly woman, the mother of the suspect, resides at the house but was not injured. Neighbors said the suspect had recently moved in to take care of her.
The investigation continues.