A 15-year-old boy has been charged by prosecutors in Washington for the tragic deaths of his parents and three of his siblings at a residence in a wealthy area near Seattle.

Andrew Humiston has been charged with five counts of first-degree murder and one count of attempted murder related to a violent incident that occurred on Monday in Fall City, according to the King County Prosecuting Attorney’s Office.

When authorities arrived, they discovered the bodies of his parents, Mark and Sarah Humiston, along with three siblings aged 7, 9, and 13.

One of his sisters, an 11-year-old girl, was injured in the shooting but has since been discharged from a hospital in the Seattle area. She escaped by pretending to be dead and then ran to a neighbor’s home for assistance, as detailed in an arrest affidavit from the Superior Court of Washington for King County.

The shooter was apprehended at the location and is currently detained at a juvenile facility. During a court session on Tuesday, he chose not to appear, and a judge confirmed there was enough evidence to hold him on the five charges of murder and one charge of attempted murder. It has been noted by law enforcement and his legal representatives that he does not have a criminal record.

The attorneys for the suspect, Molly Campera and Amy Parker, did not promptly respond to requests for comments regarding the charges filed on Thursday. They issued a statement after the first juvenile court hearing emphasizing their client’s lack of prior criminal history, noting he is a teenager who enjoys outdoor activities like mountain biking and fishing.

“The law presumes our client is innocent of these accusations, and we appreciate a judicial system that requires evidence and proof before reaching a conclusion,” their statement read.

Suspect implicated his brother in the killings, reports indicate

The initial report of the shooting came from the teenager himself, according to an arrest affidavit. Just before 5 a.m., he allegedly contacted 911 and claimed his 13-year-old brother “had shot the entire family and then killed himself.”

Investigators stated that evidence suggests the suspect shot his family members and then altered the scene to make it appear as though his brother was responsible.

“It seems that Andrew Humiston methodically killed his mother, father, two brothers, and sister, and tried to kill his other sister,” the arrest affidavit claimed. “He then manipulated the scene before first responders arrived to create the impression that [his brother] was the murderer and had subsequently taken his own life.”

During questioning, the 11-year-old girl recounted waking up to a gunshot and seeing her brother and father lying in the hallway, as stated in the affidavit. She informed authorities that she witnessed her brother being shot by the suspect.

The suspect entered her room and shot her at least once, according to the affidavit. She managed to stay quiet and waited until he left before escaping through her bedroom window and running to a neighboring house, where help was summoned.

The girl identified the gun involved as her father’s “silver Glock handgun,” according to the affidavit. She mentioned that her father stored the weapon in a small lockbox near the front door for work purposes, and she noted that the suspect was “the only one who knew the combination” to that lockbox.

A black Glock was found on the premises, as recorded in the affidavit.

When asked about any issues the suspect faced at home, she stated that “he had gotten into ‘a lot of trouble’ recently for not passing some tests in school.”

The father was an engineer, the mother was a nurse

Mark Humiston was employed as an electrical engineer at Hargis Engineers, a consulting firm in Seattle, where he was known as a mentor with a strong vision and leadership presence, as a company spokesperson shared.

“We are deeply saddened and caught off guard by the tragic events that have resulted in the loss of a valued colleague, mentor, and friend, as well as the corresponding loss of his family,” a statement from the company said.

Sarah Humiston was previously licensed as a registered nurse, according to the Washington State Department of Health. Public records indicate her license expired in 2022.

Community members gathered on Tuesday evening at the Fall City United Methodist Church to remember the Humistons and their children. Neighbors who were acquainted with the family described them as a joyful family who were well-regarded in their community.

“They were very devoted Christians who loved God. You could really tell,” neighbor Camille Sharp told KOMO News. “It’s one of those things that people always say: ‘you never expect this,’ and truly, it’s accurate.”