Herbertus Bikker (born 15 July 1915 in Wijngaarden, Netherlands – died 1 November 2008 in Haspe, Germany), also known as The Butcher of Ommen, was a Dutch war criminal.
Bikker is the alleged murderer of Dutch resistance fighter Jan Houtman [nl] who was killed, twenty-seven years old, on 17 November 1944.
Together with Klaas Carel Faber, Sander Borgers [nl] and four other convicted war criminals, he managed to escape from prison in Breda on 26 December 1952 and fled to Germany, crossing the border at Ubbergen near Cleves.
Bikker's only chance to evade prosecution and trial was to claim diminished responsibility due to illness.
However, following a breakdown and fainting in court, neurologists advised against Bikker standing trial due illness.