The man who shot dead a mother, her child, and injured two other children before killing himself in a Salt Lake City suburb had shared a number of threatening posts on social media in the days leading up to the shootings.
Jeremy Patterson shot and killed Memorez Rackley - a married woman who he had been in a relationship with - and her six-year-old son in Sandy, Utah, in a targeted attack on Tuesday afternoon as they walked home from an elementary school.
Rackley's nine-year-old son was critically injured, and a good Samaritan's daughter was also injured in the attack, which ended with Patterson turning the gun on himself.
The shooting came three days after Rackley, who was married, called in a harassment report to police Saturday morning and asked them to tell Patterson, a bodybuilder, to stop contacting her, said Sandy police Sgt Jason Nielsen.
Nielsen declined to say what the outcome of that conversation was, or detail the nature of the harassment.
Patterson shared a number of threatening Instagram posts in the days leading up to the shooting.
One photo posted two days before the shooting featured the menacing clown from the Saw films, Jigsaw, with the quote 'Let the games begin'. The Instagram post had 15 likes.
Patterson shared another post to his Facebook page in which he expressed his love for Rackley and his disappointment over her keeping their affair secret.
Authorities say married Rackley and bodybuilder Patterson were or had been in some sort of relationship and that the killings they described as targeted happened Tuesday afternoon just after Rackley picked her boys up from elementary school.
Rackley was walking about six blocks from the school when she flagged down a driver.
The unidentified female driver picked up Rackley and her boys but her car was then rammed by a pickup truck driven by Patterson, who got out and opened fire.
Also shot and injured was the driver's daughter, said Nielsen. Patterson then killed himself.
The unidentified driver then ran to a nearby house and pounded on the door. Resident Kathy Peterson found the hysterical woman and three young girls cowering, one of the girls covered in blood.
She had heard gunshots as she opened the door and brought them inside to safety.
'He's killing everybody and he's trying to kill us,' the terrified woman told Peterson through tears.
The extent and nature of Rackley and Patterson's relationship and the motive for the shooting remained unclear on Wednesday as detectives probed leads, Nielsen said.
Rackley was married to another man but Nielsen did not provide more details. Patterson was not the father of her children, he said.
Rackley's husband is doing as well as can be expected for someone dealing with the loss of the mother of his children as well as his youngest child, with another son fighting for his life, said White, who has been a family friend for 30 years.
'She was an amazing mother, she's beloved by all her friends and family ... just totally adored by the whole community,' White said about Rackley.
The shooter lived in the nearby suburb of Draper, where neighbor Patricia Briennieson described him as a muscular man who looked like a bodybuilder and had a mixed-martial arts sticker on the back window of his pickup truck.
Court records did not show previous criminal charges or requests for protective orders filed against Patterson.
Body builder shoots dead his married ex-lover and her son, six, before turning gun on himself after posting bizarre threatening messages on social media in the days before the murders Kelly Mclaughlin For Mailonline and Associated Press