Darion Aguilar mentioned killing people in his journal and expressed a “general hatred of others,” police said Wednesday. The 19-year-old wrote that he was sorry to his family for what he was planning to do, although he did not indicate precisely what that was.

The writings — described Wednesday on Twitter by Howard County police — provide the best window yet into the teen’s mind-set before he walked into a skate shop at the Mall in Columbia on Saturday, shooting and killing two employees before putting a shotgun in his mouth and pulling the trigger. But they leave unanswered perhaps the most important questions.

Why the Mall in Columbia, and the Zumiez store in particular? Why 25-year-old Tyler Johnson and 21-year-old Brianna Benlolo — Aguilar’s victims who, at least so far, appear to have no concrete connections to the young man? Howard County police say those are questions they are still probing.

“Nothing in the journal indicates why he targeted these two people or the mall in general,” Howard County police spokeswoman Sherry Llewellyn said in an e-mail.

What Aguilar’s writings — which police say came in the year leading up to the shooting — show is a teenager who was discontented, violent and self-aware. Howard County police said on Twitter that Aguilar wrote of using marijuana, expressed “thoughts of wanting to die” and even said he was “ready to die.”

Darion Marcus Aguilar. (AP)

But he never mentioned specific locations or people, police said. He wrote of needing a mental health professional, but never told his family, police said. He wrote that his plan was “set,” but he did not “indicate what he’s referring to,” police said.

An employee at Zumiez said Tuesday that Aguilar was something of a “mall rat” who occasionally spent time at the store, and Howard County police said on Twitter that Aguilar would sometimes “hang outside and smoke in small groups.” But whether he chose the mall out of mere familiarity or for some other reason remained unclear Wednesday.

No connections have emerged between Aguilar and Johnson or Benlolo, except that Aguilar and Benlolo lived near each other in College Park. Benlolo was the doting mother of a 2-year-old son, and Johnson, who lived in Ellicott City, volunteered in anti-drug efforts, friends and family members have said.

Even the path that led Aguilar to the mall is somewhat perplexing. He lived with his mom in College Park and was supposed to report to work at the Dunkin’ Donuts on Baltimore Avenue on Saturday morning. According to a missing person report released by Prince George’s County police Wednesday, he was last seen walking to work about 5:15 a.m.

But somehow, Aguilar ended up in the Montgomery County community of Burtonsville — hailing a Barwood taxi to take him to the Columbia mall, according to police and the cab company. Police said they do not know how he got there, or why he went.

Aguilar carried with him a 12-gauge shotgun — broken down inside a backpack, police said Wednesday. He had purchased it legally last month, from a Rockville gun store whose owner thought of him as “an ideal customer.” He assembled the weapon inside the Zumiez dressing room. When he emerged, he opened fire.

Police said Johnson and Benlolo were shot and killed, and another woman — 49-year-old Susan Kay Straumanis of Hanover — was shot in the foot as she stood upstairs near the store. Several others were hurt as hundreds inside the mall rushed to safety, some barricading themselves inside the many stores. Aguilar then killed himself.

Friends of Aguilar have said he seemed harmless and unremarkable; he enjoyed cooking shows and wanted to be a chef. His missing person report reflects mostly a normal teenager. He wore blue jeans, a white polo shirt covered by a gray hoodie and a gray beanie. He did not take any medications — at least none that the detective noted. He had acne.

The detective who filled out the report, though, did glean at least some hint of trouble, law enforcement officials speaking on the condition anonymity have said. Hours after the shooting, as he read Aguilar’s journal to investigate the teen’s disappearance, he came across a portion describing suicidal thoughts, officials have said. Aguilar’s mother asked the detective to put the journal down, officials have said. They began tracking his phone.

It registered at the Mall in Columbia.

Staff reporter Lynh Bui contributed to this report.

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