SALT LAKE CITY (AP) -- A Utah man accused of plotting a deadly attack on a luxury outdoor shopping center in the heart of Salt Lake City this week told investigators he planned to "randomly shoot and kill people."
Jack Harry Stiles, 42, told a crisis counselor he was preparing to "kill as many people as possible" on Wednesday because it marked the anniversary of his mother's death, authorities said.
Jail records show Stiles was booked into the Salt Lake County jail Monday and remains there on $1 million bail. The Salt Lake Legal Defender's Office said he didn't have an attorney yet.
Court documents show Stiles didn't have any weapons but was planning to buy two guns with silencers and stock up on ammunition. No motive was clear, Salt Lake County District Attorney Sim Gill said.
Police first learned of the plan Aug. 12 when a West Valley police officer was dispatched to Pioneer Valley Hospital by a crisis worker. At that point, investigators began looking into Stiles' background.
Family members told investigators the man had a history of mental illness and making threats, the district attorney said.
Gill told The Associated Press that authorities were motivated to take action by the Washington Navy Yard shooting last Monday that left a dozen people dead. That suspect had a history of violent and erratic behavior.
Stiles was "fixated" on carrying out his deadly plan Wednesday, driven by the "triggering event" of his mother's death. He may have had a delusion about their relationship that investigators haven't been able to verify from the man's ramblings, Gill said. Stiles spoke at length after being given his Miranda warning against self-incrimination.
The suspect planned to open fire at City Creek shopping center, the $1.7 billion centerpiece of Salt Lake City that spans two city blocks, charging documents say.
He also told investigators he planned to shoot "people's heads off" at a movie theater across town, and then wire a bomb underneath a transit bus.
His plan was to carry five extra magazines, and he had "scoped and mapped out the best spots" for hiding to "kill the most amount of people," charging documents say. They didn't say why Stiles wanted to do it, whether he offered a reason, or why the anniversary of his mother's death was a motivating factor.
The charging documents do not say why Stiles was at the hospital.
Barry Rose, who manages Salt Lake County's crisis line at the University of Utah's Neuropsychiatric Institute, said the crisis worker handled the situation correctly. Confidentiality goes out the window when somebody makes a credible threat to hurt others, he said.
"There is a duty to warn," Rose told the AP. "It is a requirement that we all live with."
Court records show Stiles has only one other, minor, incident on his criminal record in Utah. He had a run-in with Utah Transit Authority in October 2011 when he was charged with not paying his fare. Stiles failed to appear in court on the charge, was arrested on a warrant and booked in jail for a time. Most recently, he planned to fight the charge at a trial.
Investigators couldn't say whether Stiles was capable of carrying out his latest plan, but Gill said they decided to take the threat seriously.
"He was fixated on multiple locations, mapped them out and was revisiting those locations," Gill said Tuesday. "We couldn't take the risk. He could do anything."
Associated Press writer Brady McCombs contributed to this report.
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