Company said, 'The specific method and motives are, at this point, unknown'
TokyoReporter
More than 150 exhibitors from over 40 countries are expected to congregate at Hikarie Hall
Suspects also face drug charges
Masahiro Aoki strangled Kana Iwase, 17, to death in his residence in Edogawa Ward in 2015
Suspect pulled a knife on an employee and demanded money in broken English
Man found hanged from door, woman collapsed on bed
Suspect said, 'I learned by watching others'
Incidents took place 15 minutes apart
Suspect thrust a knife before male cashier before stealing cash from register
Suspect attempted to sexually assault victim after she refused, police say