sentences:  Dyer's downfall came when the bagged corpse of an infant was discovered in the Thames, with evidence leading to her.She was arrested on 4 April 1896, tried for the murder of infant Doris Marmon, and hanged on 10 June 1896.At the time of her death, a handful of murders were attributed to her, but there is little doubt she was responsible for many more similar deaths—possibly 400 or more, making her a candidate for history's most prolific serial killer.