(CBS/AP) KANSAS CITY, Mo. - Police said Blaec Lammers, the 20-year-old Missouri man who confessed to plotting to shoot up a "Twilight" showing and a Walmart store, was detained in 2009 for mental evaluation after threatening a store clerk.
Lammers faces three felony charges in the alleged shooting plot after his mother turned him in Thursday. Bolivar Police Chief Steve Hamilton said Saturday that Lammers was also committed for 96 hours for a mental health examination after he followed a female clerk around a Walmart store in 2009 and threatened her.
In Missouri, hospitals, law enforcement officials and private citizens can request a person be held against their will for up to 96 hours if he or she appears to be a threat to themselves or others.
"It looks like everything was done appropriately at that time," Hamilton said. "The average person will look at it and say `Why was he not charged criminally?' And the reality is the law only allows so much when a person is having some mental issues."
Lammers was charged Friday with first-degree assault, making a terroristic threat and armed criminal action in the alleged Walmart shooting plot. He is jailed in Polk County on $500,000 bond.
Polk County prosecutor Ken Ashlock said Friday that his office would file a motion asking for a mental exam of Lammers.
Lammers' mother contacted authorities Thursday saying she worried that her son "may have intentions of shooting people" during the opening weekend for the final film in the popular vampire series, police wrote in the probable cause statement.
She said her son recently purchased weapons -- two assault rifles and hundreds of bullets -- that were similar to those used by James Holmes who opened fire inside a theater in Aurora, Colo., and killed 12 people during the latest Batman movie in July.
Police wrote in the probable cause statement that Lammers was "off of his medication."
Hamilton said Saturday he didn't have details about Lammers' mental condition, although he said Friday that Lammers was under a doctor's care.
Lammers was questioned Thursday afternoon and told authorities he bought tickets to a Sunday "Twilight" screening in Bolivar and planned to shoot people inside. The town of roughly 10,000 people is about 130 miles southeast of Kansas City.
According to the probable cause statement, Lammers said he planned to "just start shooting people at random" at a Walmart store less than a mile away. He said he'd purchased two assault rifles and 400 rounds of ammunition, and if he ran out of bullets, he would "just break the glass where the ammunition is being stored and get some more and keep shooting until police arrived," investigators wrote.
Police said Lammers bought one firearm Monday and another Tuesday, then went to Aldrich to practice because he "had never shot a gun before and wanted to make sure he knew how they shot and how they functioned."
Hamilton said it appeared that Lammers obtained the firearms legally.
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