Following Nathaniel Flynn's guilty plea for murdering his grandmother Detective Chief Inspector Nick Wallen said:
"To this day we still have no idea why he attacked her. Louisa Denby was a lady, adored by her family, who had only ever shown her grandson love and kindness.
"Having murdered his Grandmother, Flynn then targeted and attacked 9-year-old Jason D`Arcy as he played in a skateboard park not far from his home. Jason was stabbed through the arm and it was only through sheer luck that he wasn't murdered by Nathaniel Flynn on that day.
"Following these very serious incidents Flynn then tried to entice an 8-year-old girl from her garden where she played and later in the evening assaulted a 59-year-old man outside his home.
"On behalf of West Yorkshire Police I would like to pay tribute to the people of Shipley who assisted the Police to quickly detain and arrest Nathaniel Flynn."