King County prosecutors on Wednesday charged a 21-year-old Woodinville-area man with premeditated first-degree murder, accusing him of arming himself with a folding knife and a hammer and fatally attacking his grandfather Sunday night.

Sean Hammonds, who was adopted by his paternal grandparents after his father died when he was 6, was detained a half mile from the stabbing scene. Hammonds is now being held in the King County Jail without bail because the charge carries a possible life sentence and Hammonds has demonstrated a propensity for violence, court and jail records show.

Killed was 65-year-old John Hammonds, who lived with his wife and grandson about 3½ miles from the stabbing scene, located in the 15200 block of Northeast 156th Street in the Hollywood Hills area, east of Woodinville, the charges say. An autopsy showed John Hammonds was stabbed 28 times in the head, neck, arm and shoulder and suffered a blunt-force injury to the top of his head, according to the charges.

Sean Hammonds is to be arraigned June 2. Court records do not yet indicate which attorney is representing him.

“The defendant in this case brutally murdered his grandfather in an entirely unprovoked attack,” Senior Deputy Prosecutor Jessica Berliner wrote in charging papers.

Berliner noted in the charges that there is an investigation into all aspects of Sean Hammonds’ mental state and how it may have contributed to the killing.


During the sheriff’s investigation, Sean Hammonds’ grandmother told detectives Hammonds was committed to Fairfax Hospital for several months over the winter and had recently stopped taking the antipsychotic medication he was prescribed, the charges say. He frequently visits other family members in Renton and at least two relatives contacted his grandmother the day before the homicide, expressing concerns about Hammonds’ behavior and commenting that he “seemed different,” according to the charges.

When Hammonds returned home Sunday afternoon, his grandmother told detectives he kept averting his eyes and grimacing, behaving in the way he did before he was committed to Fairfax, charging papers say. Fairfax Hospital is a psychiatric hospital in Kirkland.

After dinner, Hammonds agreed to join his grandparents on a walk, and the three drove to a nearby trailhead, the charges say. Based on the location of the stabbing scene, it appears the family planned to walk in Gold Creek County Park.

John Hammonds was seated in the driver’s seat of his parked vehicle when he was attacked from behind; his wife attempted to stop the assault, then ran for help as her husband got out of the car and again was attacked before collapsing in the street, the charges say. He died at the scene.

According to his grandmother’s account to investigators, the charges say Sean Hammonds “never said a word during the attack.”