Andrew Hennells threatened staff in Tesco with a knife of four years . Fifteen minutes before the raid he posted details of his plan on Facebook . Norfolk Crown Court judge deems 31-year-old 'high risk ' to the public .
Andrew Hennells threatened staff in Tesco with a knife of February 13 . Fifteen minutes before the raid he posted details of his plan on Facebook . Norfolk Crown Court judge deems 31-year-old 'high risk ' to the public .