A 19-year-old Colorado man reportedly stabbed his two younger siblings to death so he could be alone.
According to the Tribune Media Wire, Malik Vincent Murphy stabbed his siblings before also attacking his father, who had confronted his son after he heard the children's screams.
Malik fatally stabbed his sister, 5-year-old Sophia Murphy, and brother, 7-year-old Noah Murphy, in the neck as they slept, reports the Denver Post.
Malik's father, 42-year-old Jefferson Murphy, managed to eventually detain his son in the garage. Jefferson is being treated for non life-threatening injuries.
Malik later told police he often had "homicidal ideations."
"Malik Murphy stated his plan was to kill his entire family and then bury them in the backyard, and this would allow him to be alone in his residence," a police affidavit says.
He explained he had purchased the knife at a Walmart months in advance.
Malik's father also told police his son had once talked about killing family members.
In the months preceding the murder, Malik had shown signs of behavioral problems.
In March, Malik was arrested on arson charges after burning his parents' car, using "portions of a coloring book that was in the vehicle to light the gasoline on fire," reports KUSA.
After his parents asked that the charges against him be dropped, the court forced Malik to take medication. He underwent at least 12 counseling sessions after the fire and enrolled at Pikes Peak Community College.
"I think he had mental problems," Bobbie McCottrell, the children’s great-aunt, said. "That’s a tragedy. I’ve just been praying. Lord have mercy."
Neighbors said they were shocked upon hearing the news.
"I can’t even fathom what must have happened,” said Judy Barnes, who lives next door to the Murphy family. "The Murphys, they are nice people. They were adorable kids. The babies -- why, why, why? What happened?"
Some couldn't believe Malik could be capable of such a crime.
Vicky Mason, the step-grandmother of the five Murphy children, called the clan a "wonderful family."
"Malik babysat his brothers and sisters many times," she said. "He was very, very good with his brothers and sisters."
Barnes echoed similar sentiments.
"I never suspected anything that would be a cause for concern," she added. "I’d hear them carrying on, and I knew that they were a big family of five and that you’d expect squabbles. I would just shut my door. But I never imagined it could be this bad."