Matthew Pyke, of Stowmarket, Suffolk, was a British student who had lived in Nottingham since 2006 with his girlfriend, Joanna Witton.
[1][2] Pyke's murder was motivated by Heiss's obsession with Witton.
As Heiss didn't have a hotel reservation he stayed one night at the flat of Pyke and Witton.
During his last visit to the UK, on the morning of 19 September 2008 Heiss forced his way in to Pyke's flat and killed him by stabbing him 86 times.
Heiss was arrested at his home in Limburg and in May 2009 he was sentenced to a minimum of 18 years in prison.