A teenage boy unwittingly stabbed his own father to death while trying to protect his uncle outside his home, the Pierce County Sheriff’s Office said.

The fight started when a 47-year-old man showed up at an Edgewood, Washington residence and, according to police, began beating his 46-year-old brother with a crowbar in the driveway.

When two teenager brothers in the home looked outside and saw their uncle being attacked, they ran to help him, ABC affiliate KOMO-TV in Seattle reports. The 17-year-old boy stabbed the attacker several times, not knowing it was his own father, who was estranged from the family, Sheriff’s Office spokesman Sgt. Mike Blair told KOMO-TV.

Both men were rushed to area hospitals with serious injuries and, according to KOMO-TV, the boy’s father died hours later from his stab wounds.

The teen was not taken into custody.

“He was standing up for the safety of his uncle — it just so happened that it ended up being his father who was killed,” Blair said, adding, “certainly we would allow a member of our community to protect somebody who’s being feloniously assaulted, and that’s kind of where we’re at right now.

“Based on the circumstances … we were comfortable that this person is not a danger to the rest of society,” he said.

Blair said it will ultimately be up to the prosecutor to decide whether to file charges against the teen, KOMO reports, but said the facts, so far, show the teen was just trying to defend his uncle.