According to the police, there was data that there was a person with a knife within the Shinkansen on the morning of the eleventh. The man was taken into custody and handed over to the police at JR Omiya Station in Saitama Prefecture. The police are investigating the state of affairs at the moment intimately that there aren’t any accidents to passengers and crew. According to JR East, the person was on the Tohoku Shinkansen from Tokyo to Morioka, which was delayed by about 24 minutes.
Source
A person with a knife within the automotive of the Tohoku Shinkansen secured no accidents | NHK
