The killer, who came to be known as the “Phantom of Heilbronn,” was actually the result of a critical forensic error.

Editor’s Note: This story contains discussions of rape or sexual assault that may be disturbing. Reader discretion is advised. If you or someone you know has been sexually assaulted, you can find help ...

A police chief has criticised ITV over a documentary set to be broadcast - based on claims by an ex member of police staff - which alleges two elderly couples were in fact murdered by a serial killer.