A Missouri man is accused of planning a movie theater massacre at a screening of the final "Twilight" movie. Blaec Lammers, 20, was charged Friday with first-degree assault, making a terroristic threat and armed criminal action after his mother alerted police that he had purchased 400 rounds of ammunition and two assault rifles "very similar to the ones in Aurora, Colo., movie theater shooting," according to probable cause statement issued by the Bolivar, Mo., Police Department. Lammers told police that he had "homicidal thoughts" and "had purchased the firearms with the intentions of shooting up the movie theater" in Bolivar, Mo., according to probable cause statement. Lammers allegedly told the cops that he had already purchased a ticket for the Nov. 18 screening of "The Twilight Saga: Breaking Dawn -- Part 2" Lammers said he also planned to shoot up a nearby Wal-Mart store, according to the statement. He had previously threatened to stab a Wal-Mart employee in 2009. Police characterized Lammers as "being off his medication," but he was able to purchase the rifles on Monday and Tuesday this week. He then practiced shooting them in Aldrich, Mo. According to the Springfield News-Leader, Lammers is being held on $500,000 bond and does not yet have an attorney. On July 20, suspected gunman James Holmes shot up an Aurora, Colo., movie theater, killing 12 and wounding 58 on the opening weekend of the Batman movie, "The Dark Knight Rises."