Jake Evans’ confession to killing his mother and sister was chilling. “I don’t know … it’s weird. I wasn’t even really angry with them. It just kind of happened,” he told a 911 dispatcher, shortly after he shot them in their family home in Aledo, Texas. “I’ve been kind of planning on killing for a while now,” the 17-year-old said.

Evans shot his mother Jamie, 48, and sister Mallory, 15, with a .22 revolver, the New York Daily News reported. He called 911 afterward, at 12:30 a.m. on Friday. “I am pretty, I guess, evil … whatever,” he told the 911 operator.

The police dispatcher kept Evans on the phone for about 25 minutes until sheriff’s deputies arrived at the family’s house in a gated community and arrested him. Evans’ father was out of town on business, and his two other sisters weren’t home, though one was supposed to visit from college this weekend.

While on the phone, Evans asked the dispatcher about medications that might help with nightmares and thoughts about the murders. “I don’t mean to sound like a wimp or anything, but this is — wow. I’ve never, like, done anything violent in my whole life,” he said.

“I just thought it would be quick, you know?” CNHI News Service reported Evans telling the dispatcher. “I didn’t want them to feel any pain. That’s why I used a gun, but it was like everything went wrong.”

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It’s hard to imagine that anyone could be capable of killing their own family members in such an unrepentant manner. A piece in the New York Times investigated “callous-unemotional” children — who lack remorse and empathy and are at risk of becoming psychopaths as adults — earlier this year. While the research is controversial, the Times reported that many psychologists believe that psychopathy is a neurological condition, one that can be identified even in children just 5 years old.

Sheriff Larry Fowler told CNHI News Service that there was no history of mental illness, no drug or alcohol abuse and that the family seemed stable.

Evans also appears to indicate some kind of remorse, telling the dispatcher that he would never forget his sister’s screams. However, he also said he could have shot “pretty much anybody.” His motives are still a mystery, Fowler said.

Evans has been charged with capital murder and denied bail.

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