A Kentucky man charged with gunning down his retired reserve deputy father last week planted a bomb under his father’s car and left notes making clear his “intent on killing his father.”

Brandon McQuillen, 43, was arrested Thursday on charges of being a felon in possession of a weapon — he was found carrying an AR-15 rifle — and violating an emergency protective order after his father, 65-year-old John McQuillen, was found shot to death outside his Middletown apartment a day earlier.

Later on Thursday, Louisville Metro Police said he had also been charged with murder, WDRB reported.

In addition to the bomb found under his father’s car — which was detonated by the police bomb squad — investigators said they found “multiple items consistent with manufacturing explosives” in Brandon McQuillen’s car and living area.

In Brandon McQuillen’s arrest citation, police located him late Wednesday night in connection to a homicide investigation and found him in possession Wednesday of an AR-15 rifle. In court documents, police said Brandon McQuillen’s car contained handwritten notes “expressing above subjects intent on killing his father.” An explosive device was found under his father’s car, and police said “multiple items consistent with manufacturing explosives were found” in Brandon McQuillen’s car and living area.

McQuillen was given a $10,000 bond on the original charges on Thursday, but on Friday, a judge upped that bond to $1 million on the murder charge.

The McQuillens had each taken out EPOs against each other, the father in 2018 and the son last year.

Brandon McQuillen was arrested in 2020 when he allegedly chained a woman to the ceiling inside a home after she told him she didn’t want to see him anymore, as CrimeOnline reported. The arrest report says he put a chain around her neck and padlocked it to the ceiling, used a taser on her, beat her with a pool cue, and punched her in the face.

According to WDRB, he was sentenced to three years in prison on the charges in that case, which included unlawful imprisonment, assault under extreme emotional disturbance, and theft by taking. He was also found guilty at that time of violating the EPO taken out by his father.

McQuillen’s next hearing is set for March 21.