The teenager who led a deadly January assault at The Mall in Columbia did not target his victims, but planned a killing spree inspired by the 1999 Columbine High School shootings, Howard County police revealed Wednesday.

In a wide-ranging news conference that provided new details about the crime, police said Darion Marcus Aguilar was torn between violent impulses and efforts to treat his psychiatric problems. For months before the Jan. 25 incident, the 19-year-old had been frequenting websites that promoted violence and researching mass shootings on the Internet. At the same time, he was looking up suicide-help websites as he acknowledged hearing voices in his head.

Although police said Aguilar was urged by a doctor to seek psychiatric help, the violent impulses took over.

"I going to [expletive] kill you all in a couple of hours," he wrote in his journal. "I'm anxious. I hate you all so much. You are pathetic pieces of [expletive] who deserve to die. Worthless. You are all [expletive] worthless."


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He waited until 11:14 a.m. — the precise time the Columbine shootings unfolded in Littleton, Colo. — before coming out of a dressing room at a skateboard apparel store and fatally shooting two employees. After firing other shots that left a shopper wounded, he committed suicide.

The dichotomy of Aguilar's web searches, as well as his journal entries marked with apathy and anger, reinforce the need for a better understanding of mental illness, Howard County Police Chief William J. McMahon said at a press briefing. Zumiez store employees Brianna Benlolo, 21, and Tyler Johnson, 25, died in the attack.

"Nobody saw this coming," McMahon said.

Aguilar didn't see a mental health professional and didn't appear to reach any of the mental health organizations he found online, McMahon added. Police don't believe he told his mother about his symptoms, either. The 2012 shootings at Sandy Hook Elementary School in Newtown, Conn., and a movie theater in Aurora, Colo., have also raised national discussion about the evaluation and treatment of mental disorders and their link to mass killings.

"When kids are suffering from mental health issues, there seems to be a reluctance," McMahon said. "There's a stigma attached, which is also embarrassing that somehow parents have failed and I think that's the more critical question for society in general."

Computer and cell phone records were among evidence that convinced investigators that Aguilar had no connection with Johnson or Benlolo, who left behind a 2-year-old, disputing widespread speculation that he had known his victims, police said.

The new information provided little solace to the family of Johnson, who was from Ellicott City but had recently moved to Mount Airy. He had been sober for two years and was active in local 12-step programs, helping struggling addicts in recovery and looking forward to becoming a counselor.

"I don't know how you get closure when you lose a child," Johnson's aunt, Maggie Sliker, said Wednesday. "I don't think you get enough right answers."

She said details about Aguilar's mental health reflect a mental health system that's "full of holes" and said tragedies might be prevented with better treatment and evaluation. More must be done to prevent the mentally ill from obtaining guns, she said.

Benlolo family members could not be reached Wednesday.

Police said Aguilar fired off nine rounds before he put the pistol-grip Mossberg 500 to his mouth and pulled the trigger. Slung across his chest was a bandoleer with many more unused shells.

"We know more lives could've been lost," McMahon said. "He brought 54 rounds."

Even with all police have discovered, McMahon said, some questions will go unanswered, including why Aguilar chose to start at Zumiez or why he chose the mall, which many consider Columbia's "main street."

"How could something like this happen in Howard County?" the police chief asked, able to only speculate that Aguilar didn't choose a high school such as Columbine because he had already graduated.

Over the nearly 50 days since the shooting, police assigned between 12 and 30 detectives to the investigation. They conducted hundreds of interviews, read through personal journals, reviewed cell phone records, pieced together video surveillance and sifted through home computer drives and browsing histories. The ubiquity of surveillance video cameras at banks, restaurants, retail stores and the mall helped detectives piece together an almost minute-by-minute accounting of Aguilar on the day of the shooting, while police said his motivations for the attack could be traced back to early last year.

Up until then, he had been a thin, curly-haired teen who loved skateboarding and largely kept to himself. He was not a "bad kid," McMahon said. He hung around the mall, talking and smoking with friends, and occasionally was seen popping into Zumiez — though police and an employee have said he didn't interact in any meaningful way with Benlolo or Johnson.