<br /> Police suspect 41-year-old Shinji Aoba caused Japan’s worst mass killing in two decades on Thursday.<br />Aoba went to the Kyoto Animation studio in western Japan, poured fuel around the entrance and shouted “Die” as he set the building ablaze.<br />Aoba lived alone, hundreds of kilometers from the torched studio.<br />He played noisy video games non-stop, and had grabbed and threatened his neighbor just days earlier. <br />
