An Idaho resident has reportedly invoked self-defense in the fatal hatchet attack on his 69-year-old grandfather.

Jeremiah Kiley, 29, contacted 911 himself on Tuesday, following the previous day’s fatal assault on Joseph Reyes, according to a report by the Bonner County Daily Bee.

Kiley is now facing charges of second-degree murder.

Court records reveal that Kiley informed 911 operators that Reyes had been “acting erratically,” prompting him to strike the elderly man with an axe in an act of self-defense.

Kiley alleged that Reyes had threatened him with a firearm the night before during what he described as a “schizophrenic episode.” He expressed concern that Reyes might retrieve more concealed weapons from their shared home, leading him to attack in an effort to “end his suffering.”

The affidavit notes that Kiley’s demeanor shifted between calmness and aggression throughout his interview with investigators.

According to Law&Crime, Kiley is being held on a $1 million bond and is due in court again on January 21.