The man who was shot and killed by a police officer Saturday morning in Kirkland had grabbed his 18-month-old son during a fight with his girlfriend and was refusing to let him go when he was shot, law-enforcement officials said Monday.

Derek Luis Antonio Sanchez, 35, died of gunshot wounds, according to the King County Medical Examiner’s Office.

Kirkland police officers responded to reports of a domestic disturbance at a tent near Dania Furniture on 116th Street where several people were living, according to the King County Sheriff’s Office, which is handling the investigation. During a fight with his estranged girlfriend, Sanchez grabbed their child, police said.

Officers spoke with Sanchez for about an hour, according to the sheriff’s office, which described the his behavior as “erratic.” An officer shot him in the head when it appeared the boy was in danger.

He was pronounced dead at the scene. The child was medically evaluated as a precaution.